YESBAYEV, A.N.; OSPANOV, M.N. The solvability conditions for the second order nonlinear differential equation with unbounded coefficients in L2(R). Bulletin of the Karaganda University. Mathematics Series, [S. l.], v. 101, n. 1, p. 104–110, 2021. DOI: 10.31489/2021m1/104-110. Disponível em: http://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/433. Acesso em: 10 jul. 2025.