@article{MZ_1942__47_168934,
     author = {O. Perron},
     title = {\"Uber die {Approximation} stetiger {Funktionen} durch trigonometrische {Polynome}},
     journal = {Mathematische Zeitschrift},
     pages = {57--65},
     publisher = {mathdoc},
     volume = {47},
     year = {1942},
     zbl = {66.0276.01},
     url = {http://geodesic.mathdoc.fr/item/MZ_1942__47_168934/}
}