GOL’DSHTEIN, V.; UKHLOV, A. Brennan’s conjecture for composition operators on Sobolev spaces. Eurasian Mathematical Journal, [S. l.], v. 3, n. 4, p. 35–43, 2012. Disponível em: https://emj.enu.kz/index.php/main/article/view/805. Acesso em: 8 oct. 2025.