@article{AIHPA_1969__11_4_393_0,
     author = {K\"unzle, H. P.},
     title = {Degenerate lagrangean systems},
     journal = {Annales de l'institut Henri Poincar\'e. Section A, Physique Th\'eorique},
     pages = {393--414},
     publisher = {Gauthier-Villars},
     volume = {11},
     number = {4},
     year = {1969},
     mrnumber = {278586},
     zbl = {0193.24901},
     language = {en},
     url = {http://www.numdam.org/item/AIHPA_1969__11_4_393_0/}
}