000 00259nam a2200109Ia 4500
999 _c21492
_d21492
020 _a818564369
100 _aJolley E H
245 _aIntroduction to Telephony and Telegraphy
260 _c1992
_bWHEELER PUBLISHING
_aAllahabad
300 _ax+413
942 _cBK