Resources & Industries ›› 2009, Vol. 11 ›› Issue (3): 131-134.
• STUDY ON PROBLEMS • Previous Articles
WANG Hong-jun1, NIU Guo-liang1, 2
(1. School of Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China; 2. Department of Economy and Trade, Beijing College of Economy and Management, Beijing 100102, China)
(1.中国地质大学 地球科学与资源学院,北京 100083; 2.北京经济管理职业学院 经贸系,北京 100102)