Commutative regular rings
A commutative regular ring is a regular ring R = (R, + ,−,0,·,1 ) such that · is commutative: x·y = y·x.
Let R and S be commutative regular rings. A morphism from R to S is a function h : R→S that is a homomorphism: h(x + y) = h(x) + h(y) and h(x·y) = h(x)·h(y) and h(1) = 1.