This comes from veteran accounts documented through the Navy SEAL oral history collection, interviews compiled in Kevin Dockery's "Navy SEALs: A History of the Early Years," Roger Hayden's firsthand accounts of SEAL operations in the Mekong Delta, oral histories archived at the Vietnam Center and Sam Johnson Vietnam Archive at Texas Tech University, and the documented field modifications catalogued through after-action reports and equipment studies conducted by MACV and the Army's Combat Developments Command during the war.
SOURCES:
Kevin Dockery, Navy SEALs: A History of the Early Years, Berkley Books, 2001.
John Plaster, SOG: The Secret Wars of America's Commandos in Vietnam, Simon & Schuster, 1997.
Roger Hayden, firsthand accounts — cited in multiple SEAL oral history collections and documented in Dockery's research.
Vietnam Center and Sam Johnson Vietnam Archive, Texas Tech University — oral history collection, soldier letters and care package correspondence, 1965–1972.
U.S. Army Medical Command, Vietnam, medical after-action reports on immersion foot and dermatological conditions, 1966–1969, National Archives Record Group 472.
U.S. Army Combat Developments Command, equipment evaluation reports on jungle warfare gear, 1966–1968, National Archives.
Shelby Stanton, Vietnam Order of Battle, U.S. News Books, 1981 — for MACV-SOG organizational and operational context.