Altshiller-Court, N. 大学几何:面向大学和师范学院的平面几何第二课程,第二版,修订增补版 New York: Barnes and Noble, p. 18, 1952.Coxeter, H. S. M. and Greitzer, S. L. 几何再探。 Washington, DC: Math. Assoc. Amer., pp. 9-10, 1967.Dixon, R. 数学图形。 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. 圆:数学视角,修订版。 Washington, DC: Math. Assoc. Amer., pp. xiv-xv, 1995.