AISAGALIEV, S. A. The study on the calculus of variations. Journal of Mathematics, Mechanics and Computer Science, [S. l.], v. 80, n. 1, p. 21–43, 2014. Disponível em: https://bm.kaznu.kz/index.php/kaznu/article/view/35. Acesso em: 22 dec. 2024.