Require Export GeoCoq.Elements.OriginalProofs.lemma_equalanglestransitive.
Section Euclid.
Context `{Ax:euclidean_neutral_ruler_compass}.

Lemma lemma_RTcongruence :
forall A B C D E F P Q R,
RT A B C D E F -> CongA A B C P Q R ->
RT P Q R D E F.