let G1, G2 be non empty multMagma ; :: thesis: <*G1,G2*> is HGrStr-Family of {1,2}
A1: dom <*G1,G2*> = {1,2} by FINSEQ_1:4, FINSEQ_3:29;
then reconsider A = <*G1,G2*> as ManySortedSet of {1,2} by PBOOLE:def 3;
A is HGrStr-yielding

proof

let y be set ; :: according to GROUP_7:def 1 :: thesis: ( y in rng A implies y is non empty multMagma )
assume y in rng A ; :: thesis: y is non empty multMagma
then consider x being set such that
A2: ( x in dom A & A . x = y ) by FUNCT_1:def 5;
( x = 1 or x = 2 ) by A1, A2, TARSKI:def 2;
hence y is non empty multMagma by A2, FINSEQ_1:61; :: thesis: verum

end;

hence <*G1,G2*> is HGrStr-Family of {1,2} ; :: thesis: verum