The pages of Olive-Drab.com that describe U.S. clothing and equipment from World War II have been developed with the guidance of the following list of publications. The two Historical Studies from the Quartermaster General are out of print but can sometimes be found as reprints or as originals from used booksellers or on eBay.
Clothing the Soldier of World War II, QMC Historical Studies, No. 16, by Erna Risch and Thomas A. Pitkin, Historical Section, Office of the Quartermaster General, September 1946
Quartermaster Equipment for Special Forces, QMC Historical Studies, No. 5, by Thomas A. Pitkin, Historical Section, Office of the Quartermaster General, February 1944
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