CHECHIN, L.; KURMANOV, E. On the new direction in the theory of gravitational lensing. Recent Contributions to Physics, [S. l.], v. 68, n. 1, p. 13–19, 2019. DOI: 10.26577/rcph-2019-1-1115. Disponível em: https://bph.kaznu.kz/index.php/zhuzhu/article/view/1115. Acesso em: 25 feb. 2026.