http://www.dzend.com/article.asp?id=71
http://azi.javaeye.com/blog/520384
http://wenku.baidu.com/view/3590f3d6195f312b3169a589.html 太原理工论文
http://blog.csdn.net/yufangbo/archive/2009/10/29/4743219.aspx
http://blog.csdn.net/wen0006/archive/2009/03/15/3992905.aspx