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Frogman

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This article is about a type of combat diver. For other uses, seeFrogman (disambiguation).
A SEAL Delivery Team member climbs aboard a delivery vehicle before launching from the back of the submarineUSSPhiladelphia.

Afrogmanis someone who is trained inscuba divingorswimmingunderwater in a tactical capacity that includesmilitary,and in some European countries,policework. Such personnel are also known by the more formal names ofcombat diver,combatant diver,orcombat swimmer.The wordfrogmanfirst arose in the stage name the "Fearless Frogman" ofPaul Boytonin the 1870s[1]and later was claimed byJohn Spence,an enlisted member of the U.S. Navy and member of theOSS Maritime Unit,to have been applied to him while he was training in a green waterproof suit.[2]

The termfrogmanis occasionally used to refer to a civilian scuba diver. Some sport diving clubs include the wordfrogmenin their names.[citation needed]The preferred term byscubausers isdiver,[citation needed]but thefrogmanepithet persists in informal usage by non-divers, especially in the media and often refers to professional scuba divers, such as in apolice divingrole.[3]

In theU.S. militaryandintelligence community,divers trained in scuba orCCUBAwho deploy for tactical assault missions are called "combat divers".[citation needed]This term is used to commonly refer toNavy UDTs,Navy SEALs,Navy SARC,and theNavy Explosive Ordnance Disposal(EOD) units.Navy SWCChave frogmen heritage ofcombat swimmingrather than diving, one of the few and most elite units trained in this element. Other frogmen units includeMarine Raiders Marine Recon,elements of US Army Special Forces (akaGreen Berets) combat divers,Army RangersRegimental Reconnaissance Company,Air Force Pararescue,Air Force Combat Controllers,andAir Force Special Reconnaissance,as well as operatives of the CIA'sSpecial Activities Center.

In the United Kingdom, police divers have often been called "police frogmen".[4]

Some countries' tactical diver organizations include a translation of the wordfrogmanin their official names, e.g., Denmark'sFrømandskorpset;others call themselves "combat divers" or similar. Others call themselves by indefinite names such as "special group 13" and "special operations unit".[citation needed]

Many nations and some irregular armed groups deploy or have deployed combat swimmers or divers.[citation needed]

Scope of operations[edit]

Tactical diving is a branch ofprofessional divingcarried out by armed forces and tactical units. They may be divided into:[citation needed]

These groups may overlap, and the same men may serve as assault divers and work divers, such as the AustralianClearance Diving Branch (RAN).

The range of operations performed by these operatives includes:[citation needed]

  • Amphibious assault: stealthy deployment of land orboardingforces. The vast majority of combat swimmer missions are simply to get "from here to there" and arrive suitably equipped and in sufficient physical condition to fight on arrival. The deployment of tactical forces by water to assault land targets, oil platforms, or surface ship targets (as in boardings for seizure of evidence) is a major driver behind the equipping and training of combat swimmers. The purposes are many, but include feint and deception, counter-drug, law enforcement, counter-terrorism, and counter-proliferation missions.
  • Sabotage: This includes puttinglimpet mineson ships.
  • Clandestine surveying:Surveying a beachbefore atroop landing,or other forms of unauthorized underwater surveying in denied waters.
  • Clandestine underwater work, e.g.:
  • Investigating unidentified divers, or asonarecho that may be unidentified divers. Police diving work may be included.
  • Checking ships, boats, structures, and harbors for limpet mines and other sabotage; and ordinary routine maintenance in war conditions.
  • Underwater mine clearance andbomb disposal.

Typically, a diver with closed circuit oxygen rebreathing equipment will stay within a depth limit of 20 feet (6.1 m) with limited deeper excursions to a maximum of 50 feet (15 m) because of the risk of seizure due to acute oxygen toxicity.[5]The use of nitrox or mixed gas rebreathers can extend this depth range considerably, but this may be beyond the scope of operations, depending on the unit.

Mission descriptions[edit]

US and UK forces use these official definitions for mission descriptors:[citation needed]

Stealthy
keeping out of sight (e.g., underwater) when approaching the target.[citation needed]
Covert
carrying out an action of which the enemy may become aware, but whose perpetrator cannot easily be discovered or apprehended. Covert action often involves military force which cannot be hidden once it has happened. Stealth on approach, and frequently on departure, may be used.[citation needed]
Clandestine
it is intended that the enemy does not find out then or afterwards that the action has happened – for example, installingeavesdroppingdevices. Approach, installing the devices, and departure are all to be kept from the knowledge of the enemy. If the operation or its purpose is exposed, then the actor will usually make sure that the action at least remains "covert", or unattributable.[This quote needs a citation]

Defending against frogmen[edit]

Main article:Defense against swimmer incursions

Anti-frogman techniques are security methods developed to protect watercraft, ports and installations, and other sensitive resources both in or nearby vulnerable waterways from potential threats or intrusions by frogmen.

Equipment[edit]

Frogmen on clandestine operations userebreathers,as the bubbles released byopen-circuit scubawould reveal them to surface lookouts and make a noise whichhydrophonescould easily detect.[citation needed]

Origins of the name[edit]

A few different explanations have been given for the origin of the term frogman.

  • Paul Boytonadopted the stage nameThe Fearless Frogman.In the 1870s, he was a long distance swimmer who wore a rubberimmersion suit,with hood.[1]
  • In an interview with historian Erick Simmel,John Spenceclaimed that the name "frogman" was coined while he was training in a greenwaterproofsuit, "Someone saw me surfacing one day and yelled out, 'Hey, frogman!' The name stuck for all of us."[2]

History[edit]

See also:Timeline of underwater technology
A 1945 British navy frogman with complete gear, including theDavis apparatus,arebreatheroriginally conceived in 1910 byRobert Davisas an emergency submarine escape set.

In ancientRomanandGreektimes, there were instances of men swimming or diving for combat, sometimes using a hollow plant stem or a long bone as asnorkel.Diving with snorkel is mentioned byAristotle(4th century BC).[6]The earliest descriptions of frogmen in war are found inThucydides'History of the Peloponnesian War.The first instance was in 425 BC, when theAthenian fleet besieged the Spartanson the small island of Sphacteria. The Spartans managed to get supplies from the mainland by underwater swimmers towing submerged sacks of supplies. In another incident of the same war, in 415 BC, the Athenians used combat divers in the port ofSyracuse, Sicily.The Syracuseans had planted vertical wooden poles in the bottom around their port, to prevent the Atheniantriremesfrom entering. The poles were submerged, not visible above the sea level. The Athenians used various means to cut these obstacles, including divers with saws.[7]It is believed that the underwater sawing required snorkels for breathing and diving weights to keep the divers stable.[8]

Also, in the writings ofAl-Maqrizi,it is also claimed that the naval forces of theFatimid Caliphate,in an engagement withByzantineforces off the coast ofMessinahenceforth referred to as theBattle of the Straits,employed a novel strategy with strong similarities to modern-day frogmen tactics. In the writings ofHeinz Halm,who studied and translated the writings of Al-Maqrizi and other contemporary Islamic historians, it is described: "They would dive from their own ship and swim over to the enemy ship; they would fasten ropes to its rudder, along which earthenware pots containingGreek firewere then made to slide over to the enemy ship, and shattered on the sternpost. "Apparently, this tactic succeeded in destroying many Byzantine vessels, and the battle ended in a major Fatimid victory; according to the Arab historians, a thousand prisoners were taken, including the Byzantine admiral, Niketas, with many of his officers, as well as a heavy Indian sword which bore an inscription indicating that it had once belonged toMuhammad.

The HungarianChronicon Pictumclaims thatHenry III's 1052 invasion ofHungarywas defeated by a skillful diver who sabotaged Henry's supply fleet. The unexpected sinking of the ships is confirmed by German chronicles.[citation needed] On 4 November 1918, during World War I, Italian frogmen sunk the Austro-Hungarian shipViribus Unitis.

Italy started World War II with a commando frogman force already trained. Britain, Germany, the United States, and theSoviet Unionstarted commando frogman forces during World War II.[citation needed]

First frogmen[edit]

The wordfrogmanappeared first in the stage nameThe Fearless FrogmanofPaul Boyton,who since the 1870s broke records in long distance swimming to demonstrate a newly invented rubberimmersion suit,with an inflated hood.[1]

The first modern frogmen were the World War IIItalian commando frogmenofDecima Flottiglia MAS(now "ComSubIn":Comando Raggruppamento Subacquei e Incursori Teseo Tesei) which formed in 1938 and was first in action in 1940. Originally these divers were called "Uomini Gamma"because they were members of the top secret special unit called"Gruppo Gamma",which originated from the kind ofPirellirubber skin-suit[9]nicknamedmuta gammaused by these divers. Later they were nicknamed "Uomini Rana,"Italian for" frog men ", because of an underwater swimmingfrog kickstyle, similar to that of frogs, or because their fins looked like frog's feet.[10][verification needed][need quotation to verify]

This special corps used an early oxygen rebreatherscuba set,theAuto Respiratore ad Ossigeno(A.R.O), a development of theDrägeroxygenself-contained breathing apparatusdesigned for the mining industry and of theDavis Submerged Escape Apparatusmade by Siebe, Gorman & Co and by Bergomi, designed for escaping from sunken submarines. This was used from about 1920 forspearfishingby Italian sport divers, modified and adapted by the Italian navy engineers for safe underwater use and built by Pirelli and SALVAS from about 1933, and so became a precursor of the modern diving rebreather.[11][12]

For this new way of underwater diving, the Italian frogmen trained inLa Spezia,Liguria,using the newly availableGenoesefree divingspearfishing equipment;diving mask,snorkel,swimfins,and rubberdry suit,the first specially madediving watch(the luminescentPanerai), and the new A.R.O. scuba unit.[13]This was a revolutionary alternative way to dive, and the start of the transition from the usual heavy underwater diving equipment of thehard hat diverswhich had been in general use since the 18th century, to self-contained divers, free of being tethered by an air line and rope connection.[citation needed]

Wartime operations[edit]

AfterItaly declared war,theDecima Flottiglia MAS(Xª MAS) attempted several frogmen attacks on British naval bases in the Mediterranean between June 1940 and July 1941, but none were successful, because of equipment failure or early detection by British forces. On September 10, 1941, eightXª MASfrogmen were inserted by submarine close to the British harbour atGibraltar,where usinghuman torpedoesto penetrate the defences, sank three merchant ships before escaping through neutral Spain. An even more successful attack, theRaid on Alexandria,was mounted on 19 December on the harbour atAlexandria,again using human torpedoes. The raid resulted in disabling thebattleshipsHMSQueen ElizabethandHMSValianttogether with adestroyerand anoil tanker,but all six frogmen were captured.[14]Frogmen were deployed by stealth inAlgeciras,Spain, from where they launched a number oflimpet-mineattacks on Allied shipping at anchor off Gibraltar.[15]Some time later they refitted the internedItalian tankerOlterraas a mothership for human torpedoes, carrying out three assaults on ships at Gibraltar between late 1942 and early 1943, sinking six of them.[16][17]

Nazi Germanyraised a number of frogmen units under the auspices of both theKriegsmarineand theAbwehr,often relying on Italian expertise and equipment. In June 1944, aK-Verbandfrogman unit failed to destroy the bridge atBénouville,now known asPegasus Bridge,during theBattle of Normandy.In March 1945, a frogman squad from theBrandenburgerswas deployed from their base in Venice to destroy theLudendorff Bridgeover theRhinewhich had been captured by the US Army in theBattle of Remagen.Seven frogmen swam 17 kilometres (11 mi) downriver to the bridge carrying explosives, but were spotted byCanal Defence Lights.Four died, two fromhypothermia,and the rest were captured.[18]

The BritishRoyal Navyhad captured an Italian human torpedo during a failed attack on Malta; they developed a copy called theChariotand formed a unit called theExperimental Submarine Flotilla,which later merged with theSpecial Boat Service.A number of Chariot operations were attempted, most notablyOperation Titlein October 1942, an attack on theGerman battleshipTirpitz,which had to be abandoned when a storm hit the fishing boat which was towing the Chariots into position.[19]Operation Principal in January 1943 was an attack by eight Chariots onLa MaddalenaandPalermoharbours; although all the Chariots were lost, the newItalian cruiserUlpio Traianowas sunk.[20]The last and most successful British operation resulted in sinking twolinersinPhuketharbour inThailandin October 1944.[21]Royal Navy divers did not use fins until December 1942.[citation needed]

Wartime developments[edit]

In 1933 Italian companies were already producing underwater oxygen rebreathers, but the first diving set known as SCUBA was invented in 1939[22]byChristian Lambertsen,who originally called it the Lambertsen Amphibious Respirator Unit (LARU)[23]and patented it in 1940.[24]He later renamed it the Self Contained Underwater Breathing Apparatus, which, contracted to SCUBA, eventually became the generic term for both open circuit and rebreather autonomous underwater breathing equipment.

Lambertsen demonstrated it to theOffice of Strategic Services(OSS) (after already being rejected by the U.S. Navy) in a pool at a hotel in Washington D.C.[25]OSS not only bought into the concept, they hired Lambertsen to lead the program and build up the dive element of theirMaritime Unit.[25]The OSS was the predecessor of theCentral Intelligence Agency;the maritime element still exists inside the CIA'sSpecial Activities Division.[26]

John Spence,an enlisted member of the U.S. Navy, was the first man selected to join the OSS group.[2]

Postwar operations[edit]

In April 1956, CommanderLionel Crabb,a wartime pioneer of Royal Navy combat diving, disappeared during a covert inspection of the hull of theSoviet NavySverdlov-class cruiser,Ordzhonikidze,while she was moored inPortsmouth Harbour.[27]

TheShayetet 13commandos of theIsraeli Navyhave carried out a number of underwater raids on harbors. They were initially trained by veterans ofXª MASand used Italian equipment.[28]As part ofOperation Ravivin 1969, eight frogmen used two human torpedoes to enter Ras Sadat naval base nearSuez,where they destroyed twomotor torpedo boatswith mines.[29]

During the 1982Falklands War,theArgentinian Naval Intelligence Serviceplanned an attack on British warships at Gibraltar. Code namedOperation Algeciras,three frogmen, recruited from a former anti-government insurgent group, were to plant mines on the ships' hulls. The operation was abandoned when the divers were arrested by Spanish police and deported.[30]

In 1985, theFrench nuclear weapons testsatMoruroain the Pacific Ocean was being contested by environmental protesters led by theGreenpeacecampaign ship,Rainbow Warrior.TheAction Divisionof the FrenchDirectorate-General for External Securitydevised a plan tosink theRainbow Warriorwhile it was berthed in harbor atAucklandinNew Zealand.Two divers from the Division posed as tourists and attached two limpet mines to the ship's hull; the resulting explosion sank the ship and killed a Netherlands citizen on board. Two agents from the team, but not the divers, were arrested by theNew Zealand Policeand later convicted ofmanslaughter.The French government finally admitted responsibility two months later.[31]

In the U.S. Navy, frogmen were officially phased out in 1983 and all active duty frogmen were transferred to SEAL units. In 1989, during theU.S. invasion of Panama,a team of four U.S. Navy SEALs usingrebreathersconducted a combat swimmer attack on thePresidente Porras,a gunboat and yacht belonging toManuel Noriega.The commandos attached explosives to the vessel as it was tied to a pier in thePanama Canal,escaping only after being attacked with grenades.[32]Three years later duringOperation Restore Hope,members ofSEAL Team Oneswam to shore in Somalia to measure beach composition, water depth, and shore gradient ahead of a Marine landing. The mission resulted in several of the SEALs becoming ill as Somalia's waters were contaminated with raw sewage.[33]

In 1978, the U.S. Navy Special Operations Officer (1140) community was established by combining Explosive Ordnance Disposal (EOD) and Expendable Ordnance Management officers with Diving and Salvage officers. Special Ops Officers would become qualified in at lease two functional areas - normally EOD or Diving and Salvage, and Expendable Ordnance management. Officers trained in diving and salvage techniques were now allowed to follow a career pattern that took advantage of their training, and Unrestricted line officers were now permitted to specialize in salvage, with repeat tours of duty, and advanced training. Career patterns were developed to ensure that officers assigned to command were seasoned in salvage operations and well qualified in the technical aspects of their trade. "The combination gave a breadth and depth of professionalism to Navy salvage that had not been possible before."[34]

Gallery[edit]

  • A French frogman with chest counterlung loop rebreather with two breathing tubes (model "Oxygers", 1957).
    A French frogman with chest counterlung loop rebreather with twobreathing tubes(model "Oxygers", 1957).
  • Italian World War II frogman of "Gruppo Gamma"
    ItalianWorld War IIfrogman of "Gruppo Gamma"
  • Royal Navy divers in Sladen suits during World War II
    Royal Navy divers inSladen suitsduring World War II
  • USMC 2nd Reconnaissance Battalion refreshing in combatant diving with the Draeger LAR V rebreather.
    USMC2nd Reconnaissance Battalion refreshing in combatant diving with the Draeger LAR V rebreather.
  • Mannequin wearing Finnish Navy combat diver equipment. The chest rebreather is likely a Viper S-10.
    Mannequin wearing Finnish Navy combat diver equipment. The chest rebreather is likely a Viper S-10.
  • The "maiale" or "siluro a lenta corsa": first underwater transport way used by Italian frogmen in World War II
    The "maiale" or "siluro a lenta corsa": first underwater transport way used by Italian frogmen in World War II
  • Diver lock for frogmen on a type XXI U-boat.
    Diver lock for frogmen on a type XXI U-boat.
  • A Navy diver and special operator from SEAL Delivery Team (SDV) 2 perform SDV operations with the nuclear-powered guided-missile submarine USS Florida
    A Navy diver and special operator from SEAL Delivery Team (SDV) 2 perform SDV operations with the nuclear-powered guided-missile submarineUSSFlorida
  • US Navy SDV MK IX Swimmer Delivery Vehicle. Non-watertight submersible held two scuba-equipped swimmers.
    US Navy SDV MK IX Swimmer Delivery Vehicle. Non-watertight submersible held two scuba-equipped swimmers.
  • A SEAL Delivery Vehicle (SDV) is loaded aboard the Los Angeles-class fast attack submarine USS Dallas. A Dry Deck Shelter (DDS) is attached to the submarine's forward escape trunk to provide a dry environment for Navy Seals to prepare for special warfare exercises or operations. DDS is the primary supporting craft for the SDV
    A SEAL Delivery Vehicle (SDV) is loaded aboard theLos Angeles-class fast attack submarineUSSDallas.A Dry Deck Shelter (DDS) is attached to the submarine's forward escape trunk to provide a dry environment for Navy Seals to prepare for special warfare exercises or operations. DDS is the primary supporting craft for the SDV
  • A member of SEAL Delivery Vehicle Team Two prepares to launch one of the team's SEAL Delivery Vehicles from the back of USS Philadelphia on a training exercise. The SDVs are used to carry Navy SEALs from a submerged submarine to enemy targets while staying underwater and undetected.
    A member ofSEALDelivery Vehicle Team Two prepares to launch one of the team's SEAL Delivery Vehicles from the back ofUSSPhiladelphiaon a training exercise. The SDVs are used to carry Navy SEALs from a submerged submarine to enemy targets while staying underwater and undetected.
  • Navy divers and special operators attached to SEAL Delivery Team 2, perform SDV operations with USS Florida
    Navy divers and special operators attached to SEAL Delivery Team 2, perform SDV operations with USSFlorida

See also[edit]

References[edit]

  1. ^abcKehoe, Pat (2020-08-29)."Paul Boyton - Fearless Frogman from Co Kildare".Ireland Calling.Retrieved2021-06-09.
  2. ^abcPerry, Tony (2013-11-03)."John Spence dies at 95; Navy diver and pioneering WWII 'frogman'".Los Angeles Times.Retrieved2013-11-27.
  3. ^"The hidden world of police divers".2010-06-14.Retrieved2023-03-07.
  4. ^"APPENDIX'D' Relationship between the Police and the Schools".www.gov.scot.Retrieved2023-03-07.
  5. ^US Navy (2006). "19".US Navy Diving Manual, 6th revision.United States: US Naval Sea Systems Command. p. 13. Archived fromthe originalon 2008-05-02.Retrieved2008-06-15.
  6. ^Aristotle, On the Parts of Animals, ii, 16, transl. by W.Ogle, London, 1882, p. 51:
    "Just then as divers are sometimes provided with instruments for respiration, through which they can draw air from above the water, and thus may remain for a long time under the sea, so also have elephants been furnished by nature with their lengthened nostril, and, whenever they have to traverse the water, they lift this up above the surface and breathe through it."
  7. ^Thukydides, History of the Peloponnesian War, edition Ambrosio Firmin Didot, Paris, 1842, book 4, 26, and b. 7, 25.In Greek and Latin.
  8. ^Pierros D. Nick,The tactics of the enemies in the sea warfare during the Peloponnesian War.1st Pan-Corinthian Congress, Corinth, Greece, 2008. In Greek. N. Pierros is a Civil Engineer and author of historical essays.
  9. ^"Pirelli Diving Suit".www.therebreathersite.nl.Retrieved2021-03-17.
  10. ^Manuale Federale di Immersione - author Duilio Marcante
  11. ^Marí, Alejandro Sergio."Pirelli ARO WW II".Therebreathersite.nl (Janwillem Bech).
  12. ^"Rebreathers - Rebreather Autorespiratori per l'Immersione Subacquea a recupero di gas".Archived fromthe originalon 2012-07-10.
  13. ^"Libri. Teseo Tesei e gli Assaltatori della Regia Marina, di Gianni Bianchi".December 13, 2005. Archived fromthe originalon Oct 2, 2011.RetrievedSep 3,2022.
  14. ^O'Hara, Vincent P.; Cernuschi, Enrico."Frogmen against a fleet: The Italian Attack on Alexandria 18/19 December 1941".www.usnwc.edu.Naval War College Review. Archived fromthe originalon 12 February 2017.Retrieved19 September2016.
  15. ^Borghese, Valerio (1995).Sea Devils: Italian Navy Commandos in World War II.Naval Institute Press. pp. 208–09.ISBN1-55750-072-X.
  16. ^Borghese (1995), pp. 242-43
  17. ^Borghese (1995), pp. 257-59
  18. ^Blocksdorf, Helmut (2008).Hitler's Secret Commandos: Operations of the K-Verband.Barnsley, South Yorkshire: Pen & Sword Military.ISBN978-1844157839.
  19. ^"Information sheet no 101 - Attack on the Tirpitz"(PDF).www.nmrn-portsmouth.org.uk.National Museum of the Royal Navy. 2014.Retrieved26 September2016.
  20. ^Chant, Christoper."Operation Principal (iii)".codenames.info.Retrieved24 May2023.
  21. ^Hood, Jean, ed. (2007).Submarine.Conway Maritime. pp. 505–506.ISBN978-1-84486-090-6.
  22. ^Downey, Sally A. (2011-02-21)."Christian J. Lambertsen, 93, developer of the first scuba gear".The Philadelphia Inquirer.Retrieved2021-06-09.
  23. ^Shapiro, T Rees (18 February 2011)."Christian J. Lambertsen, OSS officer who created early scuba device, dies at 93".Washington Post.Retrieved16 May2011.
  24. ^"Lambertsen's patent inGoogle Patents".RetrievedSep 3,2022.[dead link]
  25. ^abShapiro, T. Rees (2011-02-19)."Christian J. Lambertsen, OSS officer who created early scuba device, dies at 93".The Washington Post.
  26. ^"CIA Special Operations Group | Special Activities Division".cia.americanspecialops.com.RetrievedSep 3,2022.
  27. ^Hoole, Rob (2007)."The Buster Crabb Enigma".mcdoa.org.uk.Minewarfare & Clearance Diving Officers' Association.Retrieved21 July2017.
  28. ^Isseroff, Ami (2005)."Zionism and Israel - Encyclopedic Dictionary - Shayetet 13".www.zionism-israel.com.Retrieved12 March2017.
  29. ^Gawrych, George Walter (2000).The Albatross of Decisive Victory: War and Policy Between Egypt and Israel in the 1967 and 1973 Arab-Israeli Wars.Praeger. p. 111.ISBN978-0313313028.
  30. ^"Operation Algeciras: How Argentina planned to attack Gibraltar".newhistories.group.shef.ac.uk.New Histories. 21 May 2011.Retrieved12 March2017.
  31. ^Reports of International Arbitral Awards: Case concerning the differences between New Zealand and France arising from the Rainbow Warrior affair(PDF).United Nations. 6 July 1986. p. 200.Retrieved12 March2017.
  32. ^Hoyt, Edwin P. (15 June 2011).SEALs at War.Random House Publishing Group. pp. 159–.ISBN978-0-307-57006-2.
  33. ^Mann, Don (5 August 2014).How to Become a Navy SEAL: Everything You Need to Know to Become a Member of the US Navy's Elite Force.Skyhorse Publishing. pp. 18–.ISBN978-1-62873-487-4.
  34. ^url=https://apps.dtic.mil/sti/citations/ADA278438

Further reading[edit]

External links[edit]

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