1. State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, China
2. College of Geoscience and Survey Engineering, China University of Mining and Technology, Beijing, China
3. School of Resources and Geosciences, China University of Mining and Technology, Xuzhou, China
4. Geosciences Department, University of Texas at Dallas, Richardson, TX, USA
5. Jiangsu Institute of Architectural Technology, Xuzhou, China
6. Yunnan Institute of Coal Geology Prospection (Emeritus), Kunming, China