1. Crichlow , W. Q. D. F. Smith R. N. Norton W. R. Corliss Worldwide radio noise levels expected in HF frequency band 10 kilocycles to 100 megacycles Boulder, Colo. 1955
2. International Radio Consultative Committee Revision of atmospheric radio noise data Documents of the IXth Plenary Assembly, Los Angeles, 1959 3 223 256 Geneva 1959
3. International Radio Consultative Committee World distribution and characteristics of atmospheric radio noise Documents of the Xth Plenary Assembly, Geneva, 1963 Geneva 1964
4. International Radio Consultative Committee Worldwide minimum external noise levels, 0.1 Hz to 100 GHz Recommendations and Reports of the CCIR, 1978, XIVth Plenary Assembly, Kyoto, 1978 1 422 427 Geneva 1978
5. International Radio Consultative Committee Man-made radio noise Recommendations and Reports of the CCIR, 1982, XVth Plenary Assembly, Geneva, 1982 6 Geneva 1983