Yanxi Liu, Robert T. Collins. Periodic Pattern Analysis under Affine Distortions Using Wallpaper Groups. In Gerald Sommer, Yehoshua Y. Zeevi, editors, Algebraic Frames for the Perception-Action Cycle, Second International Workshop, AFPAC 2000, Kiel, Germany, September 10-11, 2000, Proceedings. Volume 1888 of Lecture Notes in Computer Science, pages 241-250, Springer, 2000.