 reserve x,y,X,Y for set;
reserve G for non empty multMagma,
  D for set,
  a,b,c,r,l for Element of G;
reserve M for non empty multLoopStr;
reserve H for non empty SubStr of G,
  N for non empty MonoidalSubStr of G;

theorem
  <NAT,+,0> = multLoopStr(#NAT,addnat,0#)
proof
  set N = <NAT,+,0>;
  the multMagma of N = <NAT,+> & the_unity_wrt op(N) = un(N) by Def22,Th17;
  hence thesis by Th40,Th43;
end;
