TY  - RPRT
TI  - Basic radio propagation predictions for April 1951: three months in advance
PY  - 1951
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS BRPD-CRPL-D 77
DO  - 10.6028/NBS.BRPD-CRPL-D.77
ER  -