It is a bank of Persian puzzle
simple and beautiful
References:
http://www.hoosheparsi.ir
http://www.vase2.com
http://www.beytoote.com
http://www.math123.blogfa.com
http://www.ihoosh.ir
http://reazi89.blogfa.com
http://mehcom.com
http://math13marand.blogfa.com
http://www.koodakcity.com
http://www.havasamhast.com
http://www.topnaz.com
http://www.yasgroup.ir
http://nabeghe.blogfa.com
http://www.learning-tree.org.uk
http://www.transum.org