Takele, Astewel D., Yihenew G. Selassie, and Solomon Tekset. “Farmers’ Willingness to Pay for 2-Wheel Tractor Hiring Services in Northwestern Ethiopia: A Contingent Valuation Study”. Asian Journal of Agriculture and Food Sciences 6, no. 6 (December 15, 2018). Accessed April 25, 2024. https://ajouronline.com/index.php/AJAFS/article/view/5592.