1. http://math.truman.edu/~thammond/history/RotationalSymmetry.html Last visited: September, 2001
2. David E. Joyce http://www.clarku.edu/~djoyce/wallpaper/ Last visited: September, 2001
Electronic Sources
E-Mail Messages
1. Sandy Mike, Mjsandy@btinternet.com, Logo-programs, permission to use them was got in a personal letter
Printed Materials
Periodicals
1. Doris Schattschneider. The planar symmetry groups: their recognition and notation
Department of Math, Moravian College, Bethlehem, PA 18081
Printed Materials
Entire book
1. Field, Michael & Golubitsky, Martin. Symmetry in Chaos. Asearch for patterns in Mathematics, art and nature. Oxford University press, 1992.
2. (Rus) А.В.Волошинов. Математика и Искусство. Москва "Просвещение" 1992.
3. (Rus) С.Ю.Афонькин, А.С.Афонькина. Орнаменты народов мира. Санкт-Петербург, Кристалл 1998
4. (Rus) Ю.Я.Герчук. Что такое орнамент? Москва, Галарт, 1998.