An inverse problem for a weakly nonlinear ultraparabolic equation with three unknown functions of different arguments in the right-hand side. Neliniini Kolyvannya, [S. l.], v. 18, n. 2, p. 245–279, 2015. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/785. Acesso em: 21 jan. 2026.