@article{MM2_1972__6_154088,
     author = {Klaus Steffen},
     title = {Ein verbesserter {Existenzsatz} f\"ur {Fl\"achen} konstanter mittlerer {Kr\"ummung.}},
     journal = {Manuscripta mathematica},
     pages = {105--140},
     publisher = {mathdoc},
     volume = {6},
     year = {1972},
     zbl = {0229.53011},
     url = {http://geodesic.mathdoc.fr/item/MM2_1972__6_154088/}
}