@article{CMH_1929__1_138520,
     author = {Alexander Ostrowski},
     title = {Zur {Theorie} der konvexen {Funktionen.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {157--159},
     publisher = {mathdoc},
     volume = {1},
     year = {1929},
     zbl = {55.0143.02},
     url = {http://geodesic.mathdoc.fr/item/CMH_1929__1_138520/}
}