1. https://zhuanlan.zhihu.com/p/36621308 review Face Detection Algorithm
2. https://zhuanlan.zhihu.com/p/32702868 face detection background introduction and development of the status quo
3. https://zhuanlan.zhihu.com/p/27204728 trend face detection and recognition and analysis
4. https://zhuanlan.zhihu.com/p/25335957 face detection and depth of learning
5. https://zhuanlan.zhihu.com/p/29170512 breakdown of those "historical" human face detection algorithm change
6. https://zhuanlan.zhihu.com/p/27638463 outline progress annual face detection and recognition
7. The https://zhuanlan.zhihu.com/p/32781218 50 lines of code face detection
