reserve T for TopSpace;
reserve T for non empty TopSpace;
reserve F for Subset-Family of T;

theorem
  Int Cl Int(meet F) c= meet(Int Cl Int F)
proof
A1: Int Cl Int(meet F) c= Int(meet Cl Int F) by Th49,TOPS_1:19;
  Int(meet Cl Int F) c= meet(Int Cl Int F) by Th28;
  hence thesis by A1;
end;
