Files W.F.F. Archive Publications Army Extension Courses, Solutions-Elementary Military Cryptography, 1943; Army Extension Courses, Sub Course, Elementary Military Cryptography Introduction and Lesson 1, 1943; Army Extension Courses, Elementary Military Cryptography, Special Text No. 165, 1935 Edition; Army Extension Courses, Elementary Military Cryptography, Special Text No. 165, 1943 Edition
Army Extension Courses, Solutions, Subcourse, Elementary Military Cryptography
Army Extension Courses, Special Text No. 165, Elementary Military Cryptography; 1935 Edition
Army Extension Courses, Special Text No. 165, Elementary Military Cryptography; 1943 Edition
Army Extension Courses, Subcourse, Elementary Military Cryptography; Introduction and Lesson 1