1. Mei Lin, Yezheng Wu. Compressor Automatic Value. Xi'an: Xi'an Jiao Tong University Press, 1991: 35-41. In Chinese.
2. Yongzhang Yu. Displacement Compressors Technical Manual. Beijing: Machinery Industry Press, 2000. In Chinese.
3. Yezheng Wu. Reciprocating Compressor Mathematical Model and Application. Xi'an: Xi'an Jiao Tong University Press, 1989: 60-66. In Chinese.
4. Mei Lin, Yezheng Wu and Danqing Wu. Compressor Ring Value Principle. Beijing: Chemical Industry Press, 1982: 42-47. In Chinese.
5. Changzhong Ke, Qingfeng Nie, Ni Xiaoping, etc. Research on Movement Rules of Piston Compressor Value and Mathematical Model. Compressor Technology, 2003, 3: 8-10. In Chinese.