Berkeley, Gordon Spence creator E. Benn limited London 1934 xi, 341 p incl illus tables Traffic In Automatic Exchange (Page-13), Trunking Schemes (Page-24), Racks and Cabling (Page-70), Full Availability (Page-116), Grading (Page-141), Design Of An Automatic Exchange (Page-174), Junction Traffic (Page-208), Traffic Recording (Page-219), Other Systems (Page-237), Miscellaneous (Page-294). G. S. Berkeley Berkeley, Gordon Spence Traffic and trunking principles in automatic telephony 621.385,BER 34030021 20230802102041.0