
theorem NISOM12:
for X,Y be RealNormSpace
 st ex L be Lipschitzian LinearOperator of X,Y
      st L is isomorphism holds
  (X is Reflexive iff Y is Reflexive)
proof
   let X,Y be RealNormSpace;
   given L be Lipschitzian LinearOperator of X,Y such that
AS: L is isomorphism;
   ex K be Lipschitzian LinearOperator of Y,X st
       K = L" & K is isomorphism by AS,NORMSP_3:37;
   hence thesis by AS,NISOM11;
end;
