000 00255nam a22001097a 4500
082 _a621.382 REN'T
100 _aRENTON, R. N
_959022
245 _aTELECOMMUNICATION PRINCIPLES
260 _aLONDON
_bSIR ISAAC PITMAN
_c1964
300 _a448P
942 _cBK
999 _c569082
_d569082