GALAL AHMED ABU BAKR. The study of a particular historical event, period, or person. African Diaspora Journal of Mathematics ISSN: 1539-854X, Multidisciplinary UGC CARE GROUP I, [S. l.], v. 23, n. 1, p. 1–12, 2023. Disponível em: https://newjournalzone.in/index.php/ijmfsmr/article/view/40. Acesso em: 4 dec. 2024.