@article{MAN_1923__89_159001,
     author = {G. P\'olya},
     title = {Analytische {Fortsetzung} und konvexe {Kurven}},
     journal = {Mathematische Annalen},
     pages = {179--191},
     publisher = {mathdoc},
     volume = {89},
     year = {1923},
     zbl = {49.0225.03},
     url = {http://geodesic.mathdoc.fr/item/MAN_1923__89_159001/}
}