claim: CO2 constitutes 80% of the non-condensing greenhouse gas forcing.
evidence: However, the two other versions make sense over a principal ideal domain R: it suffices to replace "integer" by "element of the domain" and Z {\displaystyle \mathbb {Z} } by R. These two versions of the theorem are true in this context, because the proofs (except for the first existence proof), are based on Euclid's lemma and Bézout's identity, which are true over every principal domain.