1. Bourbaki, N.: �l�ments de Math�matique, Livre II: Alg�bre, Chap. 9. Formes sesquilin�aires et formes quadratiques. Paris: Hermann 1959
2. Chevalley, C.C.: The algebraic theory of spinors. New York: Columbia University Press. 1954
3. Dieudonn�, J.: La g�om�trie des groupes classiques, 3rd ed. Berlin-Heidelberg-New York: Springer 1971
4. Dieudonn�, J.: Sur les groupes classiques, 3rd ed. Paris: Hermann 1967
5. Dye, R.H.: Interrelations of symplectic and orthogonal groups in characteristic two. J. Algebra59, 202?221 (1979)