1. Daily insolation on surfaces tilted toward the equator;Liu;Trans, ASHRAE,1962
2. Hourly solar radiation data for vertical and horizontal surfaces on average days in the United States and Canada;Kusuda;Trans, ASHRAE,1962
3. An averaging technique for predicting the performance of a solar energy collector system;Strickford,1976
4. Solar radiation incident upon slopes of different orientations;Temps;Solar Energy,1977