Joint Subcommittee on Development and Research of the Edison Electric Institute and the Bell Telephone System, Edison Electric Institute, & American Telephone and Telegraph Company. Engineering reports. Charles Francis Press.

Joint Subcommittee on Development and Research of the Edison Electric Institute and the Bell Telephone System, Edison Electric Institute, and American Telephone and Telegraph Company. Engineering Reports. New York,: Charles Francis Press.

Joint Subcommittee on Development and Research of the Edison Electric Institute and the Bell Telephone System, et al. Engineering Reports. Charles Francis Press.