reserve T for non empty TopSpace;
reserve A for Subset of T;

theorem Th3:
  A in Kurat14Set A & A- in Kurat14Set A & A-` in Kurat14Set A & A-
  `- in Kurat14Set A & A-`-` in Kurat14Set A & A-`-`- in Kurat14Set A & A-`-`-`
  in Kurat14Set A
proof
A1: Cl A in Kurat14Part A & (Cl A)` in Kurat14Part A by ENUMSET1:def 5;
A2: Cl (Cl A)` in Kurat14Part A & (Cl (Cl A)`)` in Kurat14Part A by
ENUMSET1:def 5;
A3: Cl (Cl (Cl A)`)` in Kurat14Part A & (Cl (Cl (Cl A)`)`)` in Kurat14Part A
  by ENUMSET1:def 5;
  Kurat14Part A c= Kurat14Set A & A in Kurat14Part A by ENUMSET1:def 5
,XBOOLE_1:7;
  hence thesis by A1,A2,A3;
end;
