000 00305nam a2200133Ia 4500
100 _aHeld ,Gilbert
020 _a0-471-96820
250 _a2nd
942 _cBK
245 _aUnderstanding data communications
260 _aJohn Wiley & sons, England
_c1996
082 _a001.64404 Hel
300 _axx;728p
999 _c36158
_d36158