GORBACHUK, V. M. On the structure of solutions of operator-differential equations on the whole real axis. Methods of Functional Analysis and Topology, [S. l.], v. 21, n. 2, p. 170–178, 2015. Disponível em: https://zen.imath.kiev.ua/index.php/mfat/article/view/609. Acesso em: 16 dec. 2025.