@article{MAN_1921__83_158874,
     author = {J. P\'al},
     title = {Ein {Minimumproblem} f\"ur {Ovale}},
     journal = {Mathematische Annalen},
     pages = {311--320},
     publisher = {mathdoc},
     volume = {83},
     year = {1921},
     zbl = {48.0838.02},
     url = {http://geodesic.mathdoc.fr/item/MAN_1921__83_158874/}
}