A note on Rogers semilattices of families of two embedded sets in the Ershov hierarchy. Вестник КазНУ. Серия математика, механика, информатика, [S. l.], v. 68, n. 1, p. 4–13, 2011. Disponível em: https://bm.kaznu.kz/index.php/kaznu/article/view/167. Acesso em: 5 июл. 2026.