EN 29661:1991/prA:1993 信息处理.在12.7mm(0.5英寸)盒式磁带上数据交换.每毫米18磁道、1491数据字节(每英寸37871数字节)
Information processing; data interchange on 12.7 mm (0.5 in) magnetic tape cartridges; 18 tracks, 1491 data bytes per millimetre (37871 data bytes per inch) (ISO/IEC 9661:1988 technical corrigendum 2:1992)