scheme :: CIRCCMB3:sch 8
3AryDef{ F₁() -> non empty set , F₂( object , object , object ) -> Element of F₁() } :

( ex f being Function of (3 -tuples_on F₁()),F₁() st
for x, y, z being Element of F₁() holds f . <*x,y,z*> = F₂(x,y,z) & ( for f1, f2 being Function of (3 -tuples_on F₁()),F₁() st ( for x, y, z being Element of F₁() holds f1 . <*x,y,z*> = F₂(x,y,z) ) & ( for x, y, z being Element of F₁() holds f2 . <*x,y,z*> = F₂(x,y,z) ) holds
f1 = f2 ) )