ANSI X3.181 90th Edition, January 1, 1990
Information Systems - Recorded Magnetic Tape and Cartridge for Information
Interchange - 1/2 Inch (12.65 mm), Serial Serpentine, 22-Track, 6 667 bpi
(262 bpmm), and 48-Track, 10 000 bpi (394 bpmm), MFM-Encoded - Requirements
for Recording