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2. C. Brookson, GSM Security: A Description of the Services, in F. Hillebrand (ed.): GSM, Digital Cellular Mobile Communications Seminar, Budapest, 1990, 4.5-1–4.5-5.
3. ETS 300 175-7, Digital Enhanced Cordless Telecommunications (DECT); Common Interface (CI); Part 7: Security features, 1996 (2nd edition).
4. ETS 300 331, Digital European Cordless Telecommunications (DECT); DECT Authentication Module, 1995.
5. GSM 01.02 (ETR 099), Digital cellular telecommunications system (Phase 2); General description of a GSM Public Land Mobile Network (PLMN).