000 00278nam a2200121Ia 4500
008 220201s1995 xx 000 0 eng d
082 _a4.6
_bHEL
100 _aHeld,Gilbert
245 0 _aData communication
260 _aDelhi
_bMcgraw Hill
_c1995
300 _a587
942 _2ddc
999 _c34905
_d34905