Altshiller-Court, N. 大學幾何:面向大學和師範學院的平面幾何第二課程,第二版,修訂增補版 New York: Barnes and Noble, p. 18, 1952.Coxeter, H. S. M. and Greitzer, S. L. 幾何再探。 Washington, DC: Math. Assoc. Amer., pp. 9-10, 1967.Dixon, R. 數學圖形。 New York: Dover, p. 19, 1991.Kimberling, C. "Triangle Centers and Central Triangles." Congr. Numer.129, 1-295, 1998.Mackay, J. S. "Properties Concerned with the Angular Bisectors of a Triangle." Proc. Edinburgh Math. Soc.13, 37-102, 1895.Pedoe, D. 圓:數學視角,修訂版。 Washington, DC: Math. Assoc. Amer., pp. xiv-xv, 1995.