fact: Hypothesis (or1: preorder r1)(or2: preorder r2) (sr1: substrate r1 = I1)(sr2: substrate r2 = I2) (dr1: right_directed_on r1 I1) (dr2: right_directed_on r2 I2).
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat)