let G1, G2, G3 be non empty commutative multMagma ; :: thesis: <*G1,G2,G3*> is commutative HGrStr-Family of {1,2,3}
reconsider A = <*G1,G2,G3*> as HGrStr-Family of {1,2,3} ;
A is commutative
hence
<*G1,G2,G3*> is commutative HGrStr-Family of {1,2,3}
; :: thesis: verum