Congruence of Hermitian matrices over some localizations of C[z, z−1] Original Research Article

Let λ = 1 and let Cλ be the subring of the function field C(z) consisting of all functions a ε C(z) which have no pole at λ. This ring is stable under the involution * of C(z) which sends z maps to z−1 and image for all λ ε C. We solve the congruence problem for hermitian matrices over Cλ.