-(*
-notation < "x \sub \neq" with precedence 91 for @{'bsss $x}.
-interpretation "bs_of_ss" 'bsss x = (bs_of_ss _ _ _ x).
-*)
-
-(*
-lemma ss_of_bs:
- ∀O:ordered_set.∀u,v:O.
- ∀b:O squareO.\fst b ∈ [u,v] → \snd b ∈ [u,v] → {[u,v]} squareO ≝
- λO:ordered_set.λu,v:O.
- λb:O squareB.λH1,H2.〈≪\fst b,H1≫,≪\snd b,H2≫〉.
-*)
-
-(*
-notation < "x \sub \nleq" with precedence 91 for @{'ssbs $x}.
-interpretation "ss_of_bs" 'ssbs x = (ss_of_bs _ _ _ x _ _).
-*)
-