@article{MZ_1926__25_167870,
     author = {P. von Sz\'asz},
     title = {\"Uber einen {Mittelwertsatz}},
     journal = {Mathematische Zeitschrift},
     pages = {116--120},
     publisher = {mathdoc},
     volume = {25},
     year = {1926},
     zbl = {52.0226.06},
     url = {http://geodesic.mathdoc.fr/item/MZ_1926__25_167870/}
}