Calibration and validation of APSIM-Wheat and CERES-Wheat for spring wheat under rainfed conditions: Models evaluation and application. - Mukhtar Ahmed; Mustazhar Nasib Akram; Muhammad Asim; Muhammad Aslam; Fayyaz-ul Hassan; Stewart Higgins; Claudio O. Stöckle; Gerrit Hoogenboom (Comput. Electron. Agric., 2016)