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Publication date: 4 February 2005

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Fields related with sums of squares (formally real fields, Pythagorean fields, etc.) (12D15) Research exposition (monographs, survey articles) pertaining to number theory (11-02) Clifford algebras, spinors (15A66) Graded rings and modules (associative rings and algebras) (16W50) Quadratic and bilinear forms, inner products (15A63) Finite-dimensional division rings (16K20) Brauer groups (algebraic aspects) (16K50) Forms and linear algebraic groups (11Exx)

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