1. Remote Sensing Technology Institute, German Aerospace Center (DLR), 82234 Wessling, Germany
2. Chinese Academy of Surveying and Mapping, Beijing 100830, China
3. Institute for Integrated and Intelligent Systems, Griffith University, Nathan, QLD 4111, Australia
4. Independent Scientist, 7553 LL Hengelo, The Netherlands
5. Department of Space Science and Technologies, Remote Sensing Division, Akdeniz University, 07058 Antalya, Turkey