Alcantara, L. D. S. de, and M. S. Campos. “Analysis of Seasonal Aspects of Nebulosity on the Project of Fixed Photovoltaic Installations at the City of Belém, Brazil”. IEEE Latin America Transactions, vol. 17, no. 4, Nov. 2019, pp. 625-32, https://latamt.ieeer9.org/index.php/transactions/article/view/109.