@misc{ELMA_1976__31_141169,
     title = {Aufgaben.},
     journal = {Elemente der Mathematik},
     pages = {39--48},
     publisher = {mathdoc},
     volume = {31},
     year = {1976},
     url = {http://geodesic.mathdoc.fr/item/ELMA_1976__31_141169/}
}