MITROPOLSKIY, Yu. A. On the construction of an asymptotic solution of a perturbed Bretherton equation. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 50, n. 1, p. 58–71, 1998. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4972. Acesso em: 5 dec. 2025.