The Stammler hyperbola of a triangle is the Feuerbach hyperbola of its tangential triangle, and its center is the focus of the Kiepert parabola, which is Kimberling center X_110. It has trilinear equation a^2(β^2 - γ^2) + b^2(γ^2 - α^2) + c^2(α^2 - β^2) = 0. The Stammler hyperbola passes through Kimberling centers X_i for i = 1 (incenter I), 3 (circumcenter O), 6 (symmedian point K), 155, 159, 195, 399 (Parry reflection point), 610, 1498, 1740, 2574, 2575, 2916, 2917, 2918, 2929, 2930, 2931, 2935, and 2948. It also passes through the excenters J_A, J_B, and J_C, as well as through the centers of the Stammler circles.

Feuerbach hyperbola | Stammler circles | Stammler triangle