@article{CMH_1980__55_139851,
     author = {Norbert Klingen},
     title = {\"Uber schwache quadratische {Zerlegungss\"atze.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {645--651},
     publisher = {mathdoc},
     volume = {55},
     year = {1980},
     zbl = {0459.12009},
     url = {http://geodesic.mathdoc.fr/item/CMH_1980__55_139851/}
}