Cipher Code (FDIC)
Federal Deposit Insurance Corporation. Cipher Code (FDIC). Washington: Government Printing Office, 1934, https://fraser.stlouisfed.org/title/5260, accessed on April 30, 2017.
Cipher codes like the ones contained in this book were used to save on telegraphic costs and to maintain confidentiality when transmitting over public telegraph exchanges. This edition was used by FDIC bank examiners to conduct official business in the 1930s.
Government Printing Office