TY  - BOOK
AU  - Das,P.N.
TI  - An introduction to automatic telephony: for the undergraduate students of tele-communication and electrical engineering
AV  - TK6397 .D3
PY  - 1963///]
CY  - Calcutta
PB  - Modern Book Agency
KW  - Telephone, Automatic
N1  - Bibliography: p. 207-208
ER  -