00561nam a22001817a 4500 SNU 20141216122231.0 141216b xxu||||| |||| 00| 0 eng d 0818648295 HCL 621.387 COO Coover, Edwin R. Tutorial : Digital Private Branch Exchanges Edwin R. Coover Washington D C IEEE Computer Society Press 1989 ix;384p. Tutorial and Digital Private Branch Exchange , PBXs and Distributed architectures ddc HCL 40112 40112 1 0 ddc 0 0 SNUL SNUL 2014-12-16 0 621.387 COO H13778 2014-12-16 00:00:00 2014-12-16 HCL