@article{MAN_1906__62_158269,
     author = {L.P. Eisenhart},
     title = {Associate {Surfaces}},
     journal = {Mathematische Annalen},
     pages = {504--538},
     publisher = {mathdoc},
     volume = {62},
     year = {1906},
     zbl = {37.0637.03},
     url = {http://geodesic.mathdoc.fr/item/MAN_1906__62_158269/}
}