Definition Qpositive_as_well_ordering :=
  Build_well_ordering Qpositive bin_lt bin_eq bin_lt_is_order
    bin_eq_is_equality bin_lt_is_wf bin_lt_is_well_def_rht.

Lemma homographicAcc_wf : forall (a b c d : Z) (p : Qpositive), (0 < a + b)%Z -> (0 < c + d)%Z -> (0 <= a)%Z -> (0 <= b)%Z -> (0 <= c)%Z -> (0 <= d)%Z -> homographicAcc a b c d p.