000			00339nam a2200133Ia 4500
008			211209s1975 xx 000 0 und d
041			_aeng
082			_a621.382 N75 CAR
100			_aCARLSON A B
245			_aCOMMUNICATION SYSTEMS
250			_a4 ed.
260			_aNEW DELHI _bMCGRAW-HILL PUBLISHING COMPANY LIMITED _c1975
300			_a511
999			_c8741 _d8741