BS 4636-3:1971

The one-to-one correspondence between card hole patterns and the bit patterns by which a 7-bit code is represented, with special reference to the UK 7-bit code specified in BS 4730; the one-to-one correspondence between card hole patterns and the numerical series 0-11 and 1-12 (single hole punching) and the series 0-29 and 1-39 (single and double punching in a column); the card hole pattern assigned to the fraction ½ to encode a half new penny; in appendices, illustrations of the UK 7-bit data code and of the numerical sets represented on 12-row cards. See also BS 4730.