Message center-procedure - USA Voorschrift, Training Regulations, No. 160-10 Dropped and pick-up airplane messages - USA Voorschrift, Training Regulations, No. 160-6 Telegraph central office set TC-3 - USA Voorschrift, Technical Manual, 11-358 Fundamentals of telephony and manual telegraphy - USA Voorschrift, Technical Manual, 11-498 Wire telegraphy - USA Voorschrift, Technical Manual, 11-456 Fiel engineers' data handbook Signal communication for all arms and services - USA Voorschrift, Training Regulations, No. 160-5 Radio set, type SCR-132 - USA Voorschrift, Technical Regulations, No. 1210-30 Radio sets, types SCR-131 and SCR-16 - USA Voorschrift, Technical Regulations, No. 1210-50 Radio sets, types SCR-189 and SCR-190 - USA Voorschrift, Technical Regulations, No. 1210-70 Signal corps : Wire axis installation and maintenance within the division - USA Voorschrift, Training Regulations, No. 165-5 Correspondence and reports
