Elizabeth M. Middleton, Karl Fred Huemmrich, Petya K. E. Campbell, Oinsyuan Zhany, David R. Landis, Cris Garrish, Lawrence Ong, Craig Daughiry. Ground-Based Measurements and Validation Protocols for Flex. In 2018 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2018, Valencia, Spain, July 22-27, 2018. pages 3927-3930, IEEE, 2018. [doi]