Military Codes

Evidently, part of a series held by the University of Pennsylvania, cryptology collection,
consisting of seven (7) volumes:

1. American Radio Service Code No. 1;
2. Field Code No. 1;
3. Field Code No. 3;
4. The "Hudson" Code;
5. The "Allegheny" Code;
6. The "Colorado" Code;
7. The "Huron" Code.