r671	perspector, point X(264)
r672	ninecircle, orthocenter
r896	circumcircle, ninecircle
r943
r1022	circumcircle, orthocenter
r1023	orthocenter, isogonal points, isotomic points, Tarry point, point X(125)
r1034	orthocenter
r1070	circumcircle
r1336	circumcircle, poristic triangles, centroid, orthocenter, circumcenter
r1528	Euler line, inconic
r1739	circumcenter, ninecenter, perspector, point X(264), ninecircle, orthocentroidal circle
r1744	Euler line, tangential triangle, concyclic points
r2025	orthocenter, circumcircle