theorem
  for p being Point of TOP-REAL 3 holds
  sqr p = <* p`1^2, p`2^2, p`3^2 *>
  proof
    let p be Point of TOP-REAL 3;
    p = |[ p`1, p`2, p`3 ]| by EUCLID_5:3;
    hence thesis by Th15;
  end;
