@article{MAN_1904__59_158164,
     author = {Georg Hamel},
     title = {\"Uber die virtuellen {Verschiebungen} in der {Mechanik}},
     journal = {Mathematische Annalen},
     pages = {416--434},
     year = {1904},
     volume = {59},
     zbl = {35.0703.09},
     url = {http://geodesic.mathdoc.fr/item/MAN_1904__59_158164/}
}