TY  - BOOK
AU  - Ralphs,J.D.
ED  - Institution of Electrical Engineers.
TI  - Principles and practice of multi-frequency telegraphy
SN  - 0863410227
PY  - 1985///
CY  - London, UK
PB  - P. Peregrinus on behalf of the Institution of Electrical Engineers
KW  - Telegraph, Wireless
N1  - 'Errata' slip inserted; Includes bibliographical references and index
ER  -