TY - RPRT TI - Checklist of references to literature on tropospheric propagation of UHF, VHF, and SHF radio waves (1929-1959) : supplement #1 to NBS report 6001 AU - Nupen, Wilhelm PY - 1959 PB - National Bureau of Standards CY - Gaithersburg, MD SN - NBS RPT 6065 DO - 10.6028/NBS.RPT.6065 ER -