000 00311nam a2200121Ia 4500
008 230222s9999 xx 000 0 und d
082 _a621.382
100 _aThiagarajan Viswanathan
245 0 _aTelecommunication switching Systems and Networks
250 _a1
260 _bPhi New Delhi
_c2011
942 _cBK
999 _c36910
_d36910