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Hundreds of manuals and books there. People put up anything and it can usually be had as a .pdf.
Hundreds of Field Manuals and Technical manuals from the U.S, British, German, and Russians are up. Some 200 years or more old, through WW2 and today.
I have many, many amazing WW2 manuals that show in detail how stuff was done.
http://www.scribd.com/haraoi_conal probably responsible for a few hundred. Seems to have access to the library at the Command and General Staff College at Ft. Leavenworth, KS.