1.
Tleubergenov M, Azhymbaev D. Stochastical problem of Helmholtz for Birkhoff systems. M [Internet]. 2019 Mar. 30 [cited 2025 Sep. 7];93(1):78-87. Available from: http://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/279