#090501
1. http://www.cine21.com/Article/article_view.php?article_id=55954&page=2&mm=100000001
2. http://www.koreatimes.co.kr/www/news/special/2009/05/181_44086.html
3. http://navercast.naver.com/science/math/184
4. http://navercast.naver.com/science/math/106
5. http://www.cine21.com/Article/article_view.php?article_id=55782&mm=100000005