Optimizing KNN and multi-features extracted from GF-1 and GF-3 for forest above-ground biomass (AGB) estimation. - Wangfei Zhang; Mengjin Wang; Jianmin Shi; Feifei Yang; Wei Zhang; Armando Marino; Yueqiu Tian; Yongjie Ji; Han Zhao (Int. J. Digit. Earth, 2025)