Equations whose sets of solutions are invariant under a group of mappings isomorphic to a one-parameter rotation group. Neliniini Kolyvannya, [S. l.], v. 23, n. 1, p. 112–123, 2020. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/980. Acesso em: 21 jan. 2026.