1. State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing (LIESMARS), Wuhan University, Box 129, Luoyu Road, Wuhan, China
2. Department of Earth Sciences, Ndata School of Climate and Earth Sciences, Malawi University of Science and Technology, P.O. Box 5196, Limbe, Malawi
3. University of Twente, Faculty for Geo-information Science and Earth Observation (ITC), P.O. Box 217, 7500 AE Enschede, The Netherlands
4. Department of Earth Sciences, College of Earth, Ocean, and Environment, University of Delaware, Newark, Delaware, USA