reserve S for Subset of TOP-REAL 2,
  C,C1,C2 for non empty compact Subset of TOP-REAL 2,
  p,q for Point of TOP-REAL 2;
reserve i,j,k for Nat,
  t,r1,r2,s1,s2 for Real;
reserve D1 for non vertical non empty compact Subset of TOP-REAL 2,
  D2 for non horizontal non empty compact Subset of TOP-REAL 2,
  D for non vertical non horizontal non empty compact Subset of TOP-REAL 2;

theorem Th37:
  (SpStSeq S)/.3 = SE-corner S
proof
  3 in dom<*NW-corner S,NE-corner S,SE-corner S*> by FINSEQ_1:81;
  hence (SpStSeq S)/.3 = <*NW-corner S,NE-corner S,SE-corner S*>/.3 by
FINSEQ_4:68
    .= SE-corner S by FINSEQ_4:18;
end;
