@article{GDZPPN002064731,
title = {Positive-definite quadratic bundles over the plane.},
journal = {Commentarii mathematici Helvetici},
volume = {57},
year = {1982},
pages = {400-411},
zbl = {0507.14010},
url = {http://dml.mathdoc.fr/item/GDZPPN002064731}
}
Knus, M.-A.; Parimala, R.; Ojanguren, M. Positive-definite quadratic bundles over the plane.. Commentarii mathematici Helvetici, Tome 57 (1982) pp. 400-411. http://gdmltest.u-ga.fr/item/GDZPPN002064731/