35. Escher - Studio per Stelle

http://www.youtube.com/watch?v=9WHdyG9mJaI&context=C3ceadd3ADOEgsToPDskLlwtChO3oZKUxKT4LOX5P_

http://www.mcescher.com/

http://britton.disted.camosun.bc.ca/escher/jbescher.htm

http://www.mathacademy.com/pr/minitext/escher/index.asp

http://aixa.ugr.es/escher/table.html

http://zibalsc.blogspot.com/2012/01/95-galleria-di-stampe.html

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