@article{ELMA_1952__7_140584,
     author = {W. Scherrer},
     title = {Elementare {Bestimmung} der {Summe} der reziproken {Quadratzahlen.}},
     journal = {Elemente der Mathematik},
     pages = {103--106},
     publisher = {mathdoc},
     volume = {7},
     year = {1952},
     zbl = {0047.06205},
     url = {http://geodesic.mathdoc.fr/item/ELMA_1952__7_140584/}
}