000			00294nam a2200121 a 4500
003			EIA
001			4472
942			_02 _2ddc _cBK
245			_aModern data communication : _bconcepts, language and media
260			_cc1971
008			141112s1971 ck r 000 u spa d
082			_a001.64 _bD247m
999			_c10086 _d10086