@article{JRAM_1927__158_149641,
     author = {Heinrich Tietze},
     title = {\"Uber konvexe {Figuren.}},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {168--172},
     year = {1927},
     volume = {158},
     language = {de},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1927__158_149641/}
}