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[2] M. Marshall: Abstract With Rings. Queen's Papers in Pure and Applied Math. 57, Queen's University, Kingston, Ontario (1980). MR 0674651

[3] K. Szymiczek: Bilinear Algebra: An Introduction to the Algebraic Theory of Quadratic Forms. Algebra, Logic and Applications Series Vol. 7, Gordon and Breach Science Publishers 1997. MR 1478923 | Zbl 0890.11011

[4] A. Wesolowski: Automorphisms of forms of higher degrees. unpublished Ph. D. dissertation, Silesian University, Katowice (1998), in polish.