1. Monthly maps of mean daily insolation for the United States;Bennett;Solar Energy,1965
2. National Climatic Atlas of the United States;Baldwin,1968
3. Insolation Data Manual;Knapp,1980
4. SOLMET User's Manual TD-9724;National Oceanic and Atmospheric Administration,1978
5. Solar radiation and climate data for quasi-homogeneous climatic regions of the United States;Hoecker,1979