HD 466.6 S2 : methods of measurement for radio equipment used in the mobile services: part 6: selective-calling and data equipment: (IEC 489-6: 1987 + A1: 1989) / European Commitee for Electrothecnical Standardization
RM series : mobile , radiodetermination, amateur and related satellite services: CCIR recommendations (new and revised as of 22 September 1992) / International Telecommunication Union
Mobile data communications : choices and opportunities / A. P. Jowett