@article{10_4171_dm_19,
     author = {Marek Szyjewski},
     title = {An invariant of quadratic forms over schemes},
     journal = {Documenta mathematica},
     pages = {449--478},
     year = {1996},
     volume = {1},
     doi = {10.4171/dm/19},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/dm/19/}
}