https://wenku.baidu.com/view/1e37dd9a3c1ec5da51e2700f.html
https://wenku.baidu.com/view/0b325e7c69dc5022abea0091
https://wenku.baidu.com/u/lida880032?from=wenku&uid=33835f0aa300a6c30d229f04
http://cjc.ict.ac.cn/online/onlinepaper/mw-2015429144854.pdf