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(* GNU General Public License for more details.                       *)
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(* 02110-1301 USA                                                     *)
Set Automatic Coercions Import.
Set Implicit Arguments.
Unset Strict Implicit.
Require Export Field_facts.
Require Export Cfield_cat.
(** Title "Basic properties of  commutative fields." *)
Section Lemmas1.
Variable K : CFIELD.

Lemma CFIELD_com : forall x y : K, Equal (ring_mult x y) (ring_mult y x).
exact (cring_com_prf K).