1. State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, People's Republic of China
2. National Science Library, Chinese Academy of Sciences, Beijing, People's Republic of China
3. Fujian Collaborative Innovation Center for Big Data Applications in Governments, Fuzhou, People's Republic of China
4. Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, People's Republic of China
5. Faculty of Information Engineering, China University of Geosciences, Wuhan, People's Republic of China