#[deprecated(since="8.17", note="Use Coq.ZArith.Znumtheory.extgcd")]
Notation Euclid := deprecated_Euclid (only parsing).#[deprecated(since="8.17", note="Use Coq.ZArith.Znumtheory.extgcd")]
Notation Euclid_intro := deprecated_Euclid_intro (only parsing).#[deprecated(since="8.17", note="Use Coq.ZArith.Znumtheory.extgcd")]
Notation euclid := deprecated_euclid (only parsing).#[deprecated(since="8.17", note="Use Coq.ZArith.Znumtheory.extgcd")]
Notation euclid_rec := deprecated_euclid_rec (only parsing).

(* Specifications: *)
Theorem Zis_gcd_uniqueness_apart_sign : forall a b d d':Z, Zis_gcd a b d -> Zis_gcd a b d' -> d = d' \/ d = - d'.