Kolosova, S. V., V. S. Lukhanin, and M. V. Sidorov. “On Positive Solutions of Liouville-Gelfand Problem”. Journal of Mathematics, Mechanics and Computer Science 99, no. 3 (December 22, 2018): 78–91. Accessed July 3, 2024. https://bm.kaznu.kz/index.php/kaznu/article/view/460.