[1]
“SYMMETRIES OF THE HERGLOTZ VARIATIONAL PRINCIPLE IN THE CASE OF ONE INDEPENDENT VARIABLE”, Ann. Sofia Univ. Fac. Math. and Inf., vol. 100, pp. 113–122, Dec. 2011, Accessed: Feb. 04, 2026. [Online]. Available: https://annual.uni-sofia.bg/index.php/fmi/article/view/249