UAV- and Machine Learning-Based Retrieval of Wheat SPAD Values at the Overwintering Stage for Variety Screening. - Jianjun Wang; Qi Zhou; Jiali Shang; Chang Liu; Tingxuan Zhuang; Junjie Ding; Yunyu Xian; Lingtian Zhao; Weiling Wang; Guisheng Zhou; Changwei Tan; Zhongyang Huo (Remote. Sens., 2021)