STUDY OF A NONLINEAR MODEL FOR TWO PREY AND TWO PREDATORS SPECIES . Journal of the College of Basic Education, [S. l.], v. 24, n. 100, p. 73–86, 2022. DOI: 10.35950/cbej.v24i100.6480. Disponível em: https://cbej.uomustansiriyah.edu.iq/index.php/cbej/article/view/6480.. Acesso em: 6 may. 2025.