Oscillations of First Order Linear Delay Differential Equations with positive and negative coefficients. Baghdad Science Journal, Iraq, Baghdad, v. 8, n. 3, p. 806–809, 2011. DOI: 10.21123/bsj.2011.8.3.806-809. Disponível em: https://bsj.uobaghdad.edu.iq/index.php/BSJ/article/view/1295.. Acesso em: 2 may. 2024.