Das, P. N.
Carrier Current Engineering: Including Long Distance Telephony - Calcutta Modern Book Agency 1977 - 199p.
Long Line Transmission
Electric Wave
Carrier Telephone System
621.382 D229C
Carrier Current Engineering: Including Long Distance Telephony - Calcutta Modern Book Agency 1977 - 199p.
Long Line Transmission
Electric Wave
Carrier Telephone System
621.382 D229C