1. Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, P. R. China
2. College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, P. R. China
3. Shanxi Museum of Geology, Taiyuan, P. R. China
4. School of Earth Sciences and Resources, China University of Geosciences (Beijing), Beijing, P. R. China