Require Export GeoCoq.Tarski_dev.Ch13_6_Desargues_Hessenberg.
Section T14_sum.
Context `{T2D:Tarski_2D}.
Context `{TE:@Tarski_euclidean Tn TnEQD}.

Lemma sump_to_sum : forall O E E' A B C, Sump O E E' A B C -> Sum O E E' A B C.