F. De Jesus, S. S. Pascual, B. J. Passion, C. Franco, and M. R. Mallari, “Analyzing the Return-Benefit on the Use of Modern Agricultural Machinery by Rice Farmers in Nueva Ecija, Philippines Using Modern Portfolio Theory (MPT)”, Res. World Agric. Econ., vol. 6, no. 1, pp. 338–352, Dec. 2024.