TY  - RPRT
TI  - Federal Information Processing Standards Publication: telecommunications: coding and modulation requirements for duplex 600 and 1200 bitsecond modems 
PY  - 1980
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS FIPS 136
DO  - 10.6028/NBS.FIPS.136
ER  -