@article{MAN_1874__7_156638,
     author = {Lippich},
     title = {Untersuchung \"uber den {Zusammenhang} der {Fl\"achen} im {Sinne} {Riemann's}},
     journal = {Mathematische Annalen},
     pages = {212--229},
     year = {1874},
     volume = {7},
     language = {de},
     url = {http://geodesic.mathdoc.fr/item/MAN_1874__7_156638/}
}