@article{GDZPPN002269910, title = {\"Uber nichtholonome Systeme}, journal = {Mathematische Annalen}, volume = {92}, year = {1924}, pages = {33-41}, zbl = {50.0529.03}, url = {http://dml.mathdoc.fr/item/GDZPPN002269910} }
Hamel, G. Über nichtholonome Systeme. Mathematische Annalen, Tome 92 (1924) pp. 33-41. http://gdmltest.u-ga.fr/item/GDZPPN002269910/