Section GeneralMonotonicity.
Variable gf: rel -> rel.

Lemma gpaco4_mon_gen (gf' clo clo': rel -> rel) x0 x1 x2 x3 r r' rg rg'
(IN: @gpaco4 gf clo r rg x0 x1 x2 x3)
(gf_mon: monotone4 gf)
(LEgf: gf <5= gf')
(LEclo: clo <5= clo')
(LEr: r <4= r')
(LErg: rg <4= rg') :
@gpaco4 gf' clo' r' rg' x0 x1 x2 x3.