КЛЮС, І. Multipoint problem for intehrodyferentsialnyh partial differential equations, not solvable on higher derivatives. Proceedings of National Aviation University (archive), [S. l.], v. 31, n. 1, p. 189–191, 2007. DOI: 10.18372/2306-1472.31.1459. Disponível em: http://jrnl.kai.edu.ua/index.php/visnik/article/view/1459. Acesso em: 18 apr. 2026.