AZIZI, Wali Mohammad; HAYAT, Athiqullah; SHAMS, Shamsullah; ZULKIFLY, Mohammad Izat Emir. An Estimation of Underground Economy in Afghanistan Using Mathematical Fuzzy Model Based on Mean and Standard Deviation. Journal for Research in Applied Sciences and Biotechnology, [S. l.], v. 2, n. 4, p. 176–181, 2023. DOI: 10.55544/jrasb.2.4.25. Disponível em: https://www.jrasb.stallionpublication.com/index.php/jrasb/article/view/297. Acesso em: 19 oct. 2026.