Let P be a point;  Ha, Hb, Hc the orthocenters of PBC, PCA, PAB; Da, Db, Dc the isogonals of Ha, Hb, Hc in ABC. The circles {DaBC}, {DbCA}, {DcAB} have a common point, and the same happens with the circles {ADbDc}, {BDcDa}, {CDaDb}.