theorem
  for f being Permutation of the carrier of Lambda(OAS) st f is_DIL_of
  Lambda(OAS) ex f9 being Permutation of the carrier of OAS st f=f9 & f9 is
  dilatation
proof
  let f be Permutation of the carrier of Lambda(OAS);
A1: Lambda(OAS) = AffinStruct(#the carrier of OAS, lambda(the CONGR of OAS)
  #) by DIRAF:def 2;
  then reconsider f9=f as Permutation of the carrier of OAS;
  assume f is_DIL_of Lambda(OAS);
  then
A2: f is_FormalIz_of the CONGR of Lambda(OAS);
  take f9;
  thus thesis by A2,A1;
end;
