I've had these cards from the late 70's to mid 80's during my time in IBM mainframe computer operations. Of these, 6 are from IBM and 2 are from EDS (Electronic Data Systems). The SAM card from EDS is a photocopy because they didn't have enough cards to go around. The yellow System/370 Reference Summary card is still a useful tool for today's bit heads. Some things have never changed. I have a photo included of the binary interpretations of characters for both ASCII and EBCDIC. I did have 2 of these, but gave the other to a computer science major who was thrilled to get this card. It is loaded with useful information.