reserve e,u for set;
reserve X, Y for non empty TopSpace;

theorem Th10:
  for XT being Point of [:X,Y:] ex W being Point of X, T being
  Point of Y st XT=[W,T]
proof
  let XT be Point of [:X,Y:];
  the carrier of [:X,Y:] = [:the carrier of X, the carrier of Y:] by Def2;
  hence thesis by DOMAIN_1:1;
end;
