theorem Th3:
  for I,J being Program of SCMPDS holds
   stop I +* stop (I ';' J) = stop (I ';' J)
proof
  let I,J be Program of SCMPDS;
  set sI=stop I, IsI=sI, sIJ=stop (I ';' J), IsIJ= sIJ;
  dom sI c= dom sIJ by Th2;
  hence thesis by FUNCT_4:19;
end;
