A Three-Dimensional Conceptual Model for Estimating the Above-Ground Biomass of Winter Wheat Using Digital and Multispectral Unmanned Aerial Vehicle Images at Various Growth Stages. - Yongji Zhu; Jikai Liu; Xinyu Tao; Xiangxiang Su; Wenyang Li; Hainie Zha; Wenge Wu; Xinwei Li (Remote. Sens., 2023)