“Knowledge is not power.
Power alone is power.
What knowledge does is provide the means to determine where to focus that power, for maximum effect.”
- Carl von Clausewitz 
The gears of war turn throughout the Ages as combat perpetually evolves. This evolution of weapons and tactics does not include a change in the process, the intent or the results. Combat is violence and a constant series of decision (making) cycles regardless of the scale in which it is conducted.
To be ever more proficient physically and mentally is the goal, and few things outside of (historical) study and sweat bear such fruit. In search of this goal, as martialists we know the need to harness and improve our Fingerspitzengefühl , as it is an improvable skill (Richards, 2010), not some kind of third eye or an equally unattainable sixth sense. More topically specific, we also know not to go into the fight with plans to utilize particular techniques since, no plan survives first contact . A self created catalogue of pre-conceived or pre-constructed tactics or maneuvers clutters the mind and slows or stalls not only the mental processing of the battlefield environment  but the physical application of violence as well. As such, it (a busy mind) effectively shortens the Reactionary Gap  and degrades combat effectiveness.
One of those areas outside of sweat and historical study that we can turn to, as practitioners of Historical European Martial Arts (HEMA) to improve our combat proficiency is the lesson learned from USAF Colonel (ret) John R. Boyd’s OODA Loop.
Boyd is one of, if not the most important figure in modern military theory, and contributed to the development of Command and Control (C2) concepts. Those unfamiliar with him and his works should not be surprised , his name is virtually unknown . Boyd was a tactical and strategic thinker and Warrior for nearly Thirty years of honorable and decorated military service.  He was a true patriot to his country in the vein of a rebel Spartan , a maverick, an ace fighter jet pilot, as well as being a proper genius.
Boyd had proved himself as a skilled pilot in the Korean War, then trained in and then taught for the Fighter Weapons School , the USAF version of Top Gun before he went on to work at the Pentagon. Boyd created and contributed to many things of note  but the focus here is on his work on decision making.
Boyd created a timeless verbalization, a decision making model of combat called The OODA (ü-`də) Loop or Boyd Cycle. The OODA Loop (Observe, Orient, Decide and Act) is clear, concise and most importantly an effective explanation of what happens in combat. That said, since the OODA is neither linear nor prescriptive (Elkus, 2011) people still over-complicate, misunderstand, and misinterpret OODA  just as some HEMA practitioners have the tendency to overthink and overanalyze, missing the conceptual points while seeking the detailed. This of course is understandable in the academic and interpretational realms of HEMA, but in the fight it is undesirable.
If Boyd created the OODA Loop in the Thirteenth to Fifteenth centuries it surely would have been in many German fechtbuch and espoused by the fechtmeister worth his salt. The efficiency of Boyd’s combat strategy has been tried and tested. The OODA Loop was employed as doctrine by the US military and other foreign militaries almost as soon as he released his findings. Some police agencies and paramilitary organizations and a great many businesses have also used The OODA Loop with documented results.
There are two OODA Loops, the original (circa 1976) loop, and the overarching strategic command level loop developed later. The 76 Loop outlines the process of both mental and of the physical actions everyone in a fight conducts: Observe, Orient, Decide and Act.
Command and Control (C2) level OODA Loop is a more robust version of the 76 Loop used at the strategic level of command , yet it still remains assessable back down to a barroom brawl. Such is the genius and beauty of Boyd’s decision making model.
Boyd’s Loop as explained and taught  was built on experience; years of flight training, aeronautic combat instruction and dog fights. Warrior made, Warrior tested, Warrior approved and vested.
The decision making model pushes us to understand that we must seize the Vor, and in the Vor we control the fight. Boyd described operating inside an opponents’ OODA loop(s) in fighter jet combat as, “It’s like they’re moving in slow motion.”
If we defeat, break or get inside of our opponent’s OODA Loop they will be reactive and in the Nach, therefore as the fechtmeister will tell you, we win the encounter by maintaining the Vor (Lecküchner, Wallerstein, Meyer).
The OODA Loop is a series of continuous interconnected loops, which make the model more liken to a cycle of loops (Boyd Cycle, 1987). Each of the four parts are conceptually simple but with decidedly great depth as they connect and then interact with your opponent’s OODA Loop.
“Strategy is the art of making use of time and space.”
– Napoleon Bonaparte 
In Boyd’s OODA, Observation refers to use of all your senses, taking in not just your opponent and their actions but also the battle space. This observation is fed by the current unfolding situation, changes in the battle space, information outside of the current (world) view, and the rules (mandated or morally / ethically) in place. Observation is the key to the Measure or better put, it is one of the keys to maintaining the Measure. In fact fechtmeister Joachim Meyer predicates nearly every Stücken with observations.
“Knowledge rests not upon truth alone, but upon error also.“
- Carl G. Jung 
Orientation, physical or mental is fed by the raw data of every item observed; it is where the information gathered is turned into knowledge so proper decisions can be made within the context of the fight. Warriors deconstruct and analyses all the information to form a new updated mental image of the circumstance, in milliseconds. This mental processing of the raw data to useable knowledge at the speeds Police Officers, Firefighters, and Soldiers operate at is the focus of cognitive psychologist Dr. Gary Klein’s studies into high-pressure decision markers What some call intuition or even ESP is just the experienced flying through the data, when the rookie needs to evaluation more and so is slowed down (Klein, 1998).
“The cure for most obstacles is, Be decisive.”
- G. Weinberg 
The next process in the loop is (making a) decision which is that moment, however brief that one decides to go through with a particular action during an engagement.
“In war there is but one favorable moment; the great art is to seize it!”
– Napoleon Bonaparte 
The last process of the model after deciding on a course of action is actually taking that action, which no matter the outcome there is a change in the next observation process which starts at that moment.
I challenge anyone to find a HEMA exchange that does not fit into the OODA Loop. My contention, which may be to the dismay of those martial artists of every ilk that piecemeal or cherry pick techniques from various sources in search of that, “one move to end all / be all”; there is no five finger death punch, there is no ultimate sword strike or even strikes. The OODA Loop is as close as it gets, and that means an encompassing knowledge, not a secret one-strike, an experience based “snap” combat decision.
Mike Cartier of the SFL-MFFG writes:
OODA Loop Application: Tag Stücke 4: This begins with an observation “Notice when you thus in the Zufechten come with your sword in the air into the guard of the Tag and your aware that he does not hastily cut at you, so you can begin your play in the Vor” This shows us the first O in the OODA, Observe “when he does not cut hastily at you”, this is followed by the Orient phase with a quick decision to implement this Tag Stücke choice for an offensive.
Tag Stücke 3: In this Stücke you Observe the opponents attack trajectory, fall back on your Orient Phase to render you a Decision and in the blink of an eye Act upon this decision OODA in full. In the middle of this is a few possible OODA/INDES moments where the response of the opponent could dictate a different movement or response.
There could also be a many OODA loops cycling within this or any Stücke where the opponent does not play along with your game and you must react. This is a general rule in fencing, but especially true of a Stücken because we cannot get into mindless robotic performance of these Stücke, they must be expressed like music, learned but forever reactionary to the moment.
That is the genius of this OODA Loop concept; it is as applicable on the large scale as it is to the individual scale or even as a macro within than individual scale. That is because the OODA Loop means INDES in a millisecond, all these things must happen in that millisecond and that is why we must train to be better. This INDES might be in the time of a fight or in the application of political strategy or on a grand strategic military scale, in each case we make this process work for us faster than a supercomputer all the time. The training is what makes it a supercomputer, without diligent disciplined training you get a messy response from the OODA Loop.
Keith Myers of the Montgomery County Freifechters writes;
–Distance from the opponent
–What stance/position he is in
–What clothing/armour is he wearing that may be protective?
–Which foot does he have forward?
–What weapon is he carrying and what are its characteristics?
–Does he have an obvious reach or strength advantage over me?
–What is the terrain between us?
–Does he have help/colleagues?
–Does he have cover or obstacles that he can use to his advantage?
–How quickly can I reach him?
–How does my weapon match up with his?
–What stance/position will be the best to use as a starting point for my attack?
–How can I make best use of any terrain features?
–How will his clothing/armour affect my choice of attacks?
–What is his most likely response?
–Take the most advantageous stance/position
–Step/angle to close the distance the most efficiently
–Choose the timing that will work the best
–Use the appropriate attack or provoking action
Kevin Maurer of the TX-MFFG writes:
The OODA Loop can be applied to what we are attempting today in the MFFG. It is a valuable and proven method of accomplishing a mission. The OODA Loop can be viewed as applicable to our thought processes while training, learning and studying HEMA today.
Give it a try yourself, and see how many examples you can conjure up. It will improve your game by just thinking about it.
Several possible examples of the OODA loop:
Item – Two opponents square off with Longswords, Fighter A Observes fighter B assuming the high Guard of the Dach, Fighter A instantly orients themself to a Low Guard, This may progress for several more quick guard changes, opposing each other, High vs Low, Left vs Right, until the Decision is made to Act and strike to a perceived opening, so Fighter A strikes from whatever guard they were in, to the left side of Fighter B’s head.
Fighter B, Observes, Orients and makes the decision to Act and parry this attack. Fighter B is now open in a different area. Opposite to the original intended strike. Which Fighter A observes, orients, decides and acts all within a split second hopefully. So if a strike is thrown at the left side of the head, the opponent goes up and parries this, the opponent is now open in the lower right opening, which should often be immediately, quickly and nimbly attacked.
The OODA Loop is present throughout this, but can only be surmised after the fact. There is no actual thinking during the engagement, but rather a form of reactionary measure. Based on training and drilling repetitive techniques. Inculcating them into our fight vocabulary. And then actually attempting their application in Freeplay. The OODA Loop represents a Great way to imagine and help to ingrain mentally, the many techniques that Meyer taught.
Two opponents square off with Longswords. Fighter A assumes the guard of right Ox and threatens the thrust, Fighter B Observes this threat and Orientates themself to counter this threat, by assuming the right side guard.
This Observation and Orientation might well include a Decision and an Action… it all depends. But that when we are in Leger Zufechten as Joachim Meyer taught, there is a constant state of Observation and Orientation that is happening.
Basing our Decision on which guard we assume often comes from the assumed Guard of the opponent. We wish to oppose them by doing the opposite sometimes. Why close off the opening that they are threatening? Why not threaten one of their openings instead or bait them to strike to your opening they were originally threatening. For Joachim Meyer taught many examples of retaking the Vor through Indes even while still in Leger Zufechten!
Brian Cox of the IL MFFG writes;
It is surprising we have not heard of this before since this applies to the parts and times of the fight. The interchange and flexibility of the zufechten, krieg and abzug have the OODA loop in the inner workings. Getting inside your opponents OODA loop to gain the Vor is great stuff.
It is not just what you observe that is important, it is also determining what the opponent observes and just as important, what he does not observe. You and your opponent are part of the combat environment. Here is an example of how I see it:
If your opponent is consistently holding a guard incorrectly in a way that gives you an opening this is an Observation. From experience you know how to take advantage of this Observation, or you test your opponent to see how he reacts and Orient from this intel. You then begin to take advantage of this intelligence (Orient) and begin to control his actions and therefore the environment. Then you Decide when the opportunity presents its self to Act. It’s like a high speed chess match.
C. VanSlambrouck of the IL MFFG writes:
Here is the OODA Loop break down, as I see it for Meyer’s Fifth Stücken from Tag.
“In Zufechten when you come into Tag, (if you perceive that your opponent does not cut so quickly at you, you can well begin your Stücke in the Vor…”
Here Master Meyer is telling us what we observe and what to do about it, we Orient ourselves to seize the Vor, since our opponent is hesitant.
“[…]cross your hands above your head (the right over the left), so that it seems as if you intended to thrust at his face)  then let your blade drop in front of you toward your left side (Verfuhren)”.
Here we thrust, and in and of itself there is another OODA Loop happening. Although we do this thrust to mislead the opponent, to have them move their sword where we want it – to create an opening on their left, we can also Decide to actually complete the thrust and Act upon that.
Here we decide when the moment is advantageous to launch our attack. The example here is for a Scheitelhau, this is from the bind if the opponent brought their sword to bear or from a Langeort-esk position if they void the thrust stepping back.
“[…]and pull it around your head while stepping to deliver a Lang-Schneid überzwerchau targeting his Left temple or neck area. As soon as it connects, pull back around your head and deliver another überzwerchau across from your left against his right, (also at his neck). As soon as it clashes, strike with a Scheitelhau using the Lang-Schneid straight from above; and these three cuts must happen quickly in a single fluid motion.”
The intent here is three moves deep; a thrust to start controlling the flow of combat, then a überzwerchau, and another überzwerchau to get them completely in the rhythm or tempo you break with the scheitelhau. It is one move, “in a single fluid motion” and so I believe the intent is for this (scheitelhau) to hit, however Meyer always has us fencing very skilled opponents, who react well and challenge our advancement in the Art.
As soon as you Act on a Decision , the environment changes and that is Observed. To continue the example;
“Now if more space comes to you – take the opportunity”
Here Meyer confirms that our highly skilled and motivated opponent did in fact block our scheitelhau, and more importantly if we Observe the proper space, i.e. distance, we can continue to maintain the Vor by attacking before the opponent counter-attacks, but their sword is an issue .
Having observed this opportunity, your Orientation phase of the loop is small and nearly sped through, because we know from experience – “I want that sword moved, it is in my way and a hazard”.
You want this, and so Decide to Act:
“Raise your Knopf up toward your left, pulling your Langschwert around your head, take out his blade with your Flach or Kurz-Schneid, by (Unterhau) your left from below through his right toward your right by slashing upward…”
Here we begin the OODA Loop yet again, but we are so far inside the opponent OODA Loop t hey now can do nothing but embrace the suck.
We know where we and the opponent are and our respective weapons are and Observe the opening.
Orientation is the fine muscle movement at the end of the Unterhau that turns into a Glitzhau.
All things considered we decide to throw a Zornhau and end the fight, because yet again we know from experience, if we first attack the opponent’s left his right will be open for the Zorn. So in order to achieve the endstate of smacking the opponent wrathfully in the face we must create the opening. We decide to throw a Glitzhau.
“[…] so that your blade flies back around in the air (Glitzhau), and cut with the Kurz-Schneid down from above with crossed hands, by his right ear with-out hitting—though if you can reach him with the Kurz-Schneid in running past, then let it hit. Then deliver a strong Zornhau at his left side and then Abzug, cutting away from him.”
I believe working the OODA Loop, which in actually are cyclic series of loops, on the Stücken will only help our advancement as a Guild and individually as Martial Artists.
This is not a reworking or rewording of any historical master’s writings, nor some kind of new Rosetta Stone, there is nothing new under the sun and to think otherwise is a fallacy . This short paper simply describes the decision making process that all combatants make; the feedback cycle between decision-maker and the environment, how we can use this model as a tool to aid and improve our actions in the fight and in scholarly interpretations.
The OODA Loop touches upon an astounding amount of pertinent concepts of fighting (and warfare). Within the model speed, power, accuracy, initiative, the Reactionary Gap, and Situational Awareness are covered outright or by proxy. It only makes sense to attempt to aptly apply it’s principles to Historical European Martial Arts, as the data and teaching of it is already present under different terminology in the period sources.
I am all for more powerful and effective tools in my proverbial MEYER kit bag and as this model has been hailed as a highly focused guidance for effectively applying a multiple of Sun Tzu’s principles in The Art of War . It may be the missing mental link for some practitioners to fully grasp what the Fechmeisters were talking about.
 Excerpt (Hull, 2009):
“Like what one finds with many lyric-masters, who speak as if they themselves find & devise & imagine new art, such that the Art of Fencing (becomes) better and more from day to day. Yet I would like to see but one of them who may devise and do just one move or one hew which comes not from Liechtenauer’s Art.”
 “Sun Tzu gave you a rulebook, what Boyd said is way more applicable in actual thinking about tactics and strategy.” said Mike Wyly (retired) Marine colonel.
 Quote from Carl Clausewitz’s book 1832 book, “Vom Krieg”
 Important conceptual data on Fingerspitzengefühl the word is needed as it is a little used rarity outside of some military and linguistic circles:
“Fingerspitzengefühl…to have instinctive tact, to have tact and sensitivity, to have a fine instinct for something” (Schemann & Knight, 1995).
“…Fingerspitzengefühl (the feeling one has in the tips of one’s fingers) which is sometimes acquired by amateurs but is more frequently found among people who have had a great deal of experience…” (Freeman, 1997).
Excerpt (Richards, 2010)
Two points: First, Fingerspitzengefühl is a skill, so although most people can get better at it, some are going to get a lot better. Second, it’s a strange kind of skill, not for performing complicated or even dangerous tasks mystically well, but for sensing what is going on among groups of people in conflict and then influencing what happens. […]It’s important to note that while you’re building Fingerspitzengefühl, you’re also building Einheit, that is, mutual trust and a common outlook. That statement has a lot of implications.
 This is a famous US Military paraphrasing of Field Marshall (Helmuth Karl Bernhard Graf) Von Moltke’s statement, “Therefore no plan of operation extends with any degree of clarity beyond the first encounter with the main enemy force.” From his 1869 work entitled “Instructions for the Senior Troop Commanders.”
 A familiar concept in Eastern Martial Arts is the emptying of one’s mind which stems from the application of Zen to the Sword Arts. For example, Takuan Soho, a monk wrote a letter called Fudochishinmyoroku to, the sword master in service to the Shogun, Lord Yagyu Munenori explaining how to apply Zen concepts to close your defenses, “by means of the mind abiding nowhere. This is an application of the theory underlying the Zen practice of Samadhi.” (Brooks, 2011)
 The Reactionary Gap, is a Military and Law Enforcement term referring to the distance and time it takes for an individual to successfully counter of an attack. The theory first made major waves in the 1980’s where an article published in SWAT Magazine (Tueller, 1983) highlighted the concepts.
Simple Reaction Time is generally accepted to be around 220 milliseconds (Laming 1968).
 Some quotes of importance:
“John Boyd is one of the principal military geniuses of the 20th century, and hardly anyone knows his name” – John Thompson, former Canadian army officer who is managing director of the MacKenzie Institute, a Toronto-based think tank which studies global conflict.
“Ninety-nine out of 100 people don’t really understand OODA and that’s a good thing because it’s so devastating when it’s applied right, it’s scary.” (Robert Coram)
Former Commandant of the Marine Corps, General Charles C. Krulak is quoted as saying “The Iraqi army collapsed morally and intellectually under the onslaught of American and Coalition forces. John Boyd was an architect of that victory as surely as if he’d commanded a fighter wing or a maneuver division in the desert.”
(Boyd is) “the most influential military thinker since Sun Tzu” – US Defense Secretary Donald Rumsfeld
 Boyd served 30, October 1944 to 01, September 1975
 For brevity only, his Legion of Merit medals will be written about here, which is more than enough to firmly vest the phrase “Decorated” used in the article.
Although outside the normal purview of his duty assignment, Captain Boyd developed mathematically-accurate and operationally-sound tactics for effective employment of the GAR-8 Missile, devoting hundreds of hours of his off-duty time. Use of his concepts in the training of tactical aircrews has resulted in a marked improvement in operational readiness of tactical fighter squadrons within the United States Air Force, and, through training missions, has increased the combat capabilities of friendly foreign countries. (Legion of merit: April 1, 1959 – august 31, 1960. (n.d.). Retrieved from http://militarytimes.com/citations-medals-awards/citation.php?citation=58911)
Major Boyd developed the Energy Maneuverability concept of quantitatively measuring air vehicle performance in terms of total en-ergy available and its relation to the operational maneuverability and efficiency of the vehicle. Energy Maneuverability has gained wide ac-ceptance and is extensively employed throughout the Air Force. Through his own initiative and efforts, Major Boyd has made a significant contribution in the field of aeronautics. (Legion of merit: November 15, 1963 – June 30, 1966. (n.d.). Retrieved from http://militarytimes.com/citations-medals-awards/citation.php?citation=58912)
[…] the exemplary ability, diligence, and devotion to duty of Colonel Boyd in these two vital positions were instrumental factors in the resolution of many complex problems of major importance to the Air Force. His unmatched efforts were directly responsible for the development of policies and programs that were major factors in the success of military operations in Southeast Asia. The singularly distinctive accomplishments of Colonel Boyd reflect great credit upon himself and the United States Air Force. (Legion of merit: April 17, 1972 – April 11, 1973. (n.d.). Retrieved from http://militarytimes.com/citations-medals-awards/citation.php?citation=58913)
In this important assignment, the leadership, exemplary foresight, and ceaseless efforts consistently demonstrated by Colonel Boyd resulted in significant contributions to improvement of development planning, enhancement of tactical combat aircraft forces, initiation of advanced prototype efforts, refinement of the requirements process and the resolution of countless other complex problems of major impor-tance to the Air Force. The singularly distinctive accomplishments of Colonel Boyd culminate a distinguished career in the service of his country and reflect great credit upon himself and the United States Air Force. (Legion of merit: may 10, 1973 – august 31, 1975. (n.d.). Retrieved from http://militarytimes.com/citations-medals-awards/citation.php?citation=58914)
Also reference: http://www.gruntsmilitary.com/lom.shtml
 “The military services should welcome more people like Colonel John Boyd. He was something of a legend in the Pentagon for his willingness to swim against the tide and to challenge service orthodoxy“. James Schlesinger, former Secretary of Defense
 Now called the United States Air Force Warfare Center (USAFWC)
 For example:
He wrote The Aerial Attack Study
He created the Energy-Maneuverability Theory or commonly known as the EM-Theory
Paterson, F. (1998). Genghis John: Chuck Spinney’s bio of John Boyd. Robert Paterson’s Radio Weblog, Retrieved from http://radio-weblogs.com/0107127/stories/2002/12/23/genghisJohnChuckSpinneysBioOfJohnBoyd.html
He wrote New Conception for Air-to-Air Combat, It’s goal being to collapse the enemy into confusion and disorder by appearing menacing, ambiguous, chaotic, and/or misleading. (see: http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA425228)
He wrote Patterns of Conflict
He wrote A Discourse on Winning and Losing
 “The OODA is neither linear nor prescriptive[…] One doesn’t, […], sit down and think ‘What does my OODA say about ordering lunch today?’ It’s simply a model of decision-making that more or less occurs automatically.” (Elkus, 2011)
 Excerpt (Brehmer, 2005):
“Boyd’s OODA (Observe-Orient-Decide-Act) loop (Boyd, 1987) is clearly the dominant model of C2 today. Every self-respecting briefing on C2 issues has a reference to it. It is part of the Doctrines for U.S. Air Force (U.S. Air Force, 1999), U.S. Army (U.S. Army, 2003) and U.S. Navy (U.S. Navy, 1995) as well as those of other defence forces, including that of the Swedish Armed Forces (Militärstrategisk doktrin, 2002). A good description of the development of the OODA-loop can be found in Hammond (2001).”
 Here one can find an abstract of his slide presentation of the OODA in “A Discourse on Winning and Losing” (1987) http://pogoarchives.org/m/dni/john_boyd_compendium/essence_of_winning_losing.pdf
 From; Nafziger, G. (1998). Napoleon’s invasion of Russia. New York: Presidio Press.
 From; Jung, C. G. (1955). Modern man in search of a soul. London: Harcourt Harvest.
 From; Weinberg, G. (1974). The action approach. New York, NY: St. Martin’s Griffin.
 From; Luvaas, J. (2001). Napoleon on the art of war. (p. 132). New York, NY: Simon and Schuster.
 Excerpted from Master Joachim Meyer’s Fourth Stücken from Tag.
Abbott, D. H. (2008). A history of the OODA loop. In M. Safranski (Ed.), The John Boyd roundtable, debating science, strategy, and war (pp. 1-5). Ann Arbor, MI: Nimble Books LLC.
Angerman, W. S. (2004). Coming full circle with Boyd’s OODA Loop ideas. (Master’s thesis, Air force institute of technology)
Boyd, J. (1987). A discourse on winning and losing. Maxwell Air Force Base: AL: Air University Library Document No. M-U 43947. Retrieved from http://dnipogo.org/john-r-boyd/
Breen, B. (2007, December 19). What’s your intuition? Fast Company, Retrieved from http://www.fastcompany.com/magazine/38/klein.html
Brehmer, B. (2005). The dynamic OODA loop: Amalgamating Boyd’s OODA Loop and the cybernetic approach to command and control. 10th International Command and Control Research and Technology Symposium
Brooks, J. Time, space & mind: the three dimensions of the reactionary gap. Retrieved from http://fightingarts.com/reading/get_author.php?author=Jeff Brooks
Cartier, M. (2007, June 15). Parts of the fight in meyer: evidence for re-evaluation of the view of the parts of the fight in Meyer. Retrieved from http://freifechter.com/meyer_parts.cfm
Clausewitz, C. V., & Rapoport, A. (1982). On war. Penguin Classics; Abridged edition.
Dute, K. (2006, Fall). Biography Boyd, John R. Retrieved from http://www.pabook.libraries.psu.edu/palitmap/bios/Boyd__John.html
Döbringer, H., (2005). Cod.hs.3227a or Hanko Döbringer fechtbuch from 1389. (Lindholm, D. Trans). Original work published 1389. Retrieved from http://thearma.org/Manuals/Dobringer_A5_sidebyside.pdf
Elkus, A. (2011, November 01). I’ve got the OODA blues. CTOvision.com. Retrieved from http://ctovision.com/2011/11/ive-got-the-ooda-blues/
Freeman, C. W. (1997). The Diplomat’s Dictionary. (Revised ed.). Washington, DC: United States Institute of Peace.
Hammond, G., (2004). The mind of war: John Boyd and american security. Washington: Smithsonian Press.
Hammonds, K. (2002, May 31). The strategy of the fighter pilot. Retrieved from http://www.fastcompany.com/magazine/59/pilot.html
Hightower, T. (n.d.). Boyd’s o.o.d.a loop and how we use it. Tactical Response, Retrieved from http://www.tacticalresponse.com/d/node/226
Howe, P. R. (2011). Leadership and training for the fight, using special operations principles to succeed in law enforcement, business, and war. Skyhorse Pub Co Inc.
Hull, J. (2009, October 19). Directives not director. MFFG: Guest Articles on Various HEMA Subjects, Retrieved from http://freifechter.com/article6.cfm
Klein, G. A. (1998). Sources of power, how people make decisions. Cambridge, MA: The MIT Press. Retrieved from http://books.google.com/books?id=nn1kGwL4hRgC&lpg=PP1&pg=PP1
Meyer, J. (1570). Gründtliche beschreibung der Adeligen und Ritterlichen Kunst des Fechtens. Straßburg: Thiebolt Berger
Osinga, F.P.B. (2007, July 13). A discourse on winning and losing: introducing core ideas and themes of Boyd’s “Theory of intellectual evolution and growth“. Retrieved from http://www.ausairpower.net/APA-Boyd-Papers.html
Osinga, F. P. B. (2009). Science, strategy and war, the strategic theory of John Boyd. Taylor & Francis.
Paret, P., & Carver, M. (1986). Makers of modern strategy, from Machiavelli to the nuclear age. Princeton: Princeton Univ Pr.
Richards, C. (2003). A swift, elusive sword: what if Sun Tzu and John Boyd did a national defense review? Center for Defense Information.
Richards, C. (2008). The origins of John Boyd’s a discourse on winning and losing. In M. Safranski (Ed.), The John Boyd roundtable, debating science, strategy, and war (pp. 6-10). Ann Arbor, MI: Nimble Books LLC.
Richards, C. (2010, August 17). Developing the touch. Retrieved from http://fasttransients.wordpress.com/
Safranski, M., & Barnett, T. P. M. (2010). The John Boyd roundtable, debating science, strategy, and war. Nimble Books LLC.
Schemann, H., & Knight, P. (1995). German/English dictionary of idioms: Idiomatik deutsch-englisch. (1 ed., p. 241). New York, NY: Routledge.
Soho, T., & Wilson, W. S. (2011). The unfettered mind: Writings from a zen master to a master swordsman. Retrieved from
Tueller, D. (1983, March). How close is too close? SWAT Magazine, Retrieved from http://www.theppsc.org/Staff_Views/Tueller/How.Close.htm