Improving Accuracy of Herbage Yield Predictions in Perennial Ryegrass with UAV-Based Structural and Spectral Data Fusion and Machine Learning. - Joanna Pranga; Irene Borra-Serrano; Jonas Aper; Tom De Swaef; An Ghesquiere; Paul Quataert; Isabel Roldán-Ruiz; Ivan A. Janssens; Greet Ruysschaert; Peter Lootens (Remote. Sens., 2021)