r:CRng, a:(|r|). a Ideal of r   

latex

Up	rings 1
Definitions of Statement	Rng, CRng, r+gp, S Ideal of R
Definitions	t.1, |g|, x f y, P  Q, r+gp, P & Q, S Ideal of R, t  T, , x:A. B(x), Rng, CRng
Lemmas	crng wf, rng times wf, rng car wf, add grp of rng wf, subgrp p wf