Hilda P. Hudson, Ruler & Compasses, pp. 95-98.

Roger A. Johnson, Advanced Euclidean Geometry, pp. 117-121.

Dan Pedoe, Circles, A Mathematical View, pp. 21-23.

Dan Pedoe, Geometry, A Comprehensive Course, pp. 101-105.

Julius Petersen, Methods and Theories for the Solution of Geometrical Constructions Applied to 400 Problems, pp. 94-95.