000 00295nam a2200121Ia 4500
008 220201s1980 xx 000 0 eng d
082 _bBIS
100 _aN.N. Biswas
245 0 _aPrinciples of telegraphy
260 _aBombay
_bmedia promoters publication
_c1980
300 _a185
942 _2ddc
999 _c22703
_d22703