Guidelines for carrier phone systems
Subtitle: installation, maintenance, and improvement
By: by James C. Cawley.
Series: A Bureau of Mines handbook
Publisher: U.S. Dept. of the Interior
Published: 1981
Place of publication: Avondale, Md
Language: eng
Number of pages: 69
Subjects: Mine communication systems.; Electric lines -- Carrier transmission.
Notes: Bibliography: p. 67.