GORYUNOV, A. S.; MIKHAILETS, V. A. Regularization of two-term differential equations with singular coefficients by quasiderivatives. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 63, n. 9, p. 1190–1205, 2011. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2797. Acesso em: 5 dec. 2025.