“Description of Positively Existentially Closed Models in Any Class of -Structures With Unary Predicates Axiomatizable by Any H-Universal Sentence”. ҚазҰУ Хабаршысы. Математика, механика, информатика сериясы, vol. 69, no. 2, June 2011, pp. 39-43, https://bm.kaznu.kz/index.php/kaznu/article/view/193.