MRC内存管理

http://www.cnblogs.com/kenshincui/p/3870325.html

http://www.jianshu.com/p/8b1ed04b3ba9

http://blog.youkuaiyun.com/weiwangchao_/article/details/7376189

http://www.cnblogs.com/seesea125/p/3175431.html

http://blog.sina.com.cn/s/blog_71715bf8010166u2.html

http://mobile.51cto.com/iphone-388823.htm

http://www.cnblogs.com/ydhliphonedev/archive/2012/03/12/2392569.html

http://blog.youkuaiyun.com/lonelyroamer/article/details/7666851

http://www.cnblogs.com/mybkn/articles/3123967.html

http://www.2cto.com/kf/201308/237863.html