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3. Pogany, D., Ward, D. S. and Lof, G. O. G., The economics of solar heating and cooling systems, ISES Congress, Los Angeles, Extended Abstracts, Paper 12/1, July 1975.
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5. Braun, G. W., Davis, E. S., French, R. L. and Hirshberg, A. S., Assessment of solar heating and cooling for an electric utility company, ISES Congress, Los Angeles, Extended Abstracts, Paper 12/5, July 1975.