Vasileva N, Lilov L. A TENSORIAL FORM OF LAGRANGE’S EQUATIONS. Ann. Sofia Univ. Fac. Math. and Inf. [Internet]. 1991 Dec. 12 [cited 2024 Nov. 24];82(2):249-86. Available from: https://ftl5.uni-sofia.bg./index.php/fmi/article/view/546