theorem
  L is upper-bounded implies <.p.) = [#p,Top L#]
proof
  assume
A1: L is upper-bounded;
  let q;
A2: q in <.p.) iff p [= q by FILTER_0:15;
  p [= Top L & q [= Top L by A1,LATTICES:19;
  hence thesis by A2,Th62;
end;
