1. Hough, P. V.C. 1962, Method and means for recognising complex patterns, U.S. Patent No. 3,069,654
2. Generalising the Hough transform to detect arbitrary shapes;Ballard;Pattern Recog. Lett.,1981
3. Shape Detection in Computer Vision using the Hough Transform;Leavers,1992
4. The Radon Transform and some of its Applications;Deans,1993
5. The Radon transform and its application to shape parametrisation in machine vision;Leavers;Image and Vision Computing,1987