@article{MZ_1929__29_168077,
     author = {Jessen B\"orge},
     title = {\"Uber konvexe {Punktmengen} konstanter {Breite.}},
     journal = {Mathematische Zeitschrift},
     pages = {378--380},
     publisher = {mathdoc},
     volume = {29},
     year = {1929},
     zbl = {54.0797.04},
     url = {http://geodesic.mathdoc.fr/item/MZ_1929__29_168077/}
}