Section Compatibility.
Variable gf: rel -> rel.
Hypothesis gf_mon: monotone0 gf.
Structure compatible0 (clo: rel -> rel) : Prop :=
compat0_intro {
compat0_mon: monotone0 clo;
compat0_compat : forall r,
clo (gf r) <0= gf (clo r);
}.
Structure wcompatible0 clo : Prop :=
wcompat0_intro {
wcompat0_mon: monotone0 clo;
wcompat0_wcompat : forall r,
clo (gf r) <0= gf (gupaco0 gf clo r);
}.

Lemma wcompat0_compat clo
(WCMP: wcompatible0 clo) :
compatible0 (gupaco0 gf clo).