00261nam a2200109Ia 4500008004100000041000800041082002000049100001200069245005300081260000900134300000800143211209s1979    xx            000 0 und d  aeng  a621.382 N79 LLO  aLLOYD T  aTHEORY AND PROBLEMS OF ELECTRONIC COMMUNICATION   c1979  a138