@article{MOMA_1967__71_177400,
     author = {P. Noordzij},
     title = {\"Uber das {Produkt} von vier reellen, homogenen, linearen {Formen.}},
     journal = {Monatshefte f\"ur Mathematik},
     pages = {436--445},
     publisher = {mathdoc},
     volume = {71},
     year = {1967},
     zbl = {0164.05303},
     url = {http://geodesic.mathdoc.fr/item/MOMA_1967__71_177400/}
}