@article{MAN_1889__34_157449,
     author = {B\"acklund},
     title = {Zur {Wellentheorie} gasartiger {Mittel}},
     journal = {Mathematische Annalen},
     pages = {371--446},
     publisher = {mathdoc},
     volume = {34},
     year = {1889},
     zbl = {21.1192.01},
     url = {http://geodesic.mathdoc.fr/item/MAN_1889__34_157449/}
}