@article{AIHPA_1992__56_1_27_0,
     author = {Echeverr{\'\i}a Enr{\'\i}quez, A. and Mu\~noz Lecanda, M. C.},
     title = {Variational calculus in several variables : a hamiltonian approach},
     journal = {Annales de l'I.H.P. Physique th\'eorique},
     pages = {27--47},
     publisher = {Gauthier-Villars},
     volume = {56},
     number = {1},
     year = {1992},
     mrnumber = {1149867},
     zbl = {0737.70009},
     language = {en},
     url = {http://www.numdam.org/item/AIHPA_1992__56_1_27_0/}
}