@book{MSM_1925__1__1_0,
     author = {Appell, Paul},
     title = {Sur une forme g\'en\'erale des \'equations de la dynamique},
     series = {M\'emorial des sciences math\'ematiques},
     publisher = {Gauthier-Villars},
     number = {1},
     year = {1925},
     language = {fr},
     url = {http://www.numdam.org/item/MSM_1925__1__1_0/}
}