Nonlinear Noether second order boundary-value problems in the critical case. Neliniini Kolyvannya, [S. l.], v. 16, n. 2, p. 261–269, 2013. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/697. Acesso em: 21 jan. 2026.