中图分类法:	G220.7-09 版次：
著者:	Medoff, Norman J.,
题名:	Now media : [ the evolution of electronic communication /] / ,
版次:	Fourth edition.
载体形态:	xii, 436 pages : illustrations (some color) ; 29 cm
附注:	"A Focal Press Book"--from cover.
主题词:	Broadcasting History.
主题词:	Mass media History.
主题词:	Digital media History.
主题词:	Telecommunication History.
主要责任者:	Kaye, Barbara K.,