Podraza, Roman, and Andrzej Dominik. “Credibility Coefficients for Objects of Rough Sets”. Studia Informatica. System and information technology 7, no. 1-2 (December 15, 2006): 93–104. Accessed April 27, 2024. https://czasopisma.uph.edu.pl/studiainformatica/article/view/2853.