Odd orthogonal matrices and the non-injectivity of the Vaserstein symbol
The Vaserstein symbol maps the unimodular triples (over any commutative ring) modulo addition operations to the elementary symplectic Witt group. It is bijective for two-dimensional rings. It is not imjective for some three-dimensional rings. The paper gives new interesting examples of such rings.
scientific article; zbMATH DE number 6910266