KHALIL, S. A.; FATHY, A. M. An Empirical Method for Estimating Global Solar Radiation over Egypt. Acta Polytechnica, Prague, Czech Republic, v. 48, n. 5, 2008. DOI: 10.14311/1057. Disponível em: https://ojs.cvut.cz/ojs/index.php/ap/article/view/1057. Acesso em: 2 apr. 2025.