Several are out of print editions: 1) Hoffschmidt's "Know Your .45 Auto Pistols", 2) Campbell's "The '03 Era", 3) Kenyon's "Luger: The Multi-National Pistol", 4) Gortz and Walter's "The Navy Luger", 5) Clawson's "Colt .45 Government Models (Commercial Series)", 6) Rankin's "Walther Models PP and PPK", 7-8) Rankin's "Walther" (Vol. II, III), 9) White and Munhall's "Cartridge Headstamp Guide (First Revision)", 10) Kenyon's "Lugers at Random", 11) Mathews' "Firearms Identification" (Vol. I, II, III), with photocopies of Curtis' "9mm Parabellum Headstamp and Case Type Guide".