Require Export GeoCoq.Tarski_dev.Ch11_angles.
Section T12_1.
Context `{TnEQD:Tarski_neutral_dimensionless_with_decidable_point_equality}.

Lemma Par_strict_perm :
forall A B C D,
Par_strict A B C D ->
Par_strict A B C D /\ Par_strict B A C D /\ Par_strict A B D C /\ Par_strict B A D C /\
Par_strict C D A B /\ Par_strict C D B A /\ Par_strict D C A B /\ Par_strict D C B A.