حسب الله ابراهيم م. Optimism and its Relationship with LeadershipBehavior of Coaches of Football League. College of Basic Education Research Journal, [S. l.], v. 7, n. 2, p. 277–293, 2008. Disponível em: https://jeh.uomosul.edu.iq/index.php/berj/article/view/37893. Acesso em: 27 oct. 2025.