Words and waves: an introduction to electrical communications / A. H. W. Beck. Beck, A. H. W. (Arnold Hugh William), 1916- Telecommunication. TK5101 .B33 1967b 621.3815 Bibliography: p. 245-246. London : Weidenfeld & Nicolson, c1967. c1967. 1967 Text 255 p. : eng World university library