http://hi.baidu.com/%D3%EA%BA%F3%B5%C4%B5%AD%C0%B6%C7%E7%BF%D5/blog/item/de68531da804189987d6b6b2.html
http://www.flashas.net/asbc/20090908/4493.html
http://www.cnblogs.com/zongwan/archive/2010/07/06/1772079.html