@article{MZ_1960__74_169895,
     author = {P. Bergau and J. Mennicke},
     title = {\"Uber topologische {Abbildungen} der {Brezelfl\"ache} vom {Geschlecht} 2.},
     journal = {Mathematische Zeitschrift},
     pages = {414--435},
     publisher = {mathdoc},
     volume = {74},
     year = {1960},
     zbl = {0144.22903},
     url = {http://geodesic.mathdoc.fr/item/MZ_1960__74_169895/}
}