00475nam a22001817a 4500 NUST - PNEC 20170116181028.0 150918b xxu||||| |||| 00| 0 eng d LIBRARY 621.38775 BER 10936 Berkeley, G. S Traffic and trunking principles in automatic telephony G. S Berkeley 2nd ed. 1949 10938 Telephone, Automatic EL, Comm ddc BK 67637 67637 0 0 ddc 0 0 PNEC PNEC WING-B 0000-00-00 0 621.38775 BER PNECLIB-001164 2015-09-18 0000-00-00 BK