A. HAMMODAT, A.; علاء; A. BILAL, A.; علی; S. MOHAMMED, A.; اکرم. Some basic properties of idempotent matrices. Journal of Education and Science (JES), [S. l.], v. 21, n. 4, p. 124–130, 2008. DOI: 10.33899/edusj.2008.56102. Disponível em: https://rjps.uomosul.edu.iq/index.php/edusj/article/view/18248. Acesso em: 4 aug. 2025.