@article{MAN_1871__3_156505,
     author = {Cayley},
     title = {On the deficiency of certain surfaces},
     journal = {Mathematische Annalen},
     pages = {526--529},
     publisher = {mathdoc},
     volume = {3},
     year = {1871},
     zbl = {03.0291.02},
     url = {http://geodesic.mathdoc.fr/item/MAN_1871__3_156505/}
}