[4] Liu Yi. Research on Internal Control Audit of China National Petroleum Corporation [D]. Beijing: ChinaUniversity of Petroleum (Beijing), 2005
[5]罗正东.中国石油天然气集团公司内部审计程序研究[D].北京:中国石油大学(北京),2011.
[6] Xu Qinghong. Research on Internal Control Auditof China National Petroleum Corporation [D]. Shanghai:Shanghai University of Finance and Economics, 2002
[7] Zhang Jihai. Research on Internal Audit of In-vestment Decisions of China National Petroleum Corpora-tion [D]. China University of Petroleum (Beijing), 2002
