Fatemeh Afsharnia and  Mohammad Amin Asoodar and  Abbas Abdeshahi,  The Effect of Failure Rate on Repair and Maintenance Costs of Four Agricultural Tractor Models.   journal   = {International Journal of Agricultural and Biosystems Engineering}, [online]. World Academy of Science, Engineering and Technology.
    March 2014, vol. 87(3). 286 - 290
    [viewed 19 September 2024]. Available from: https://publications.waset.org/pdf/9997982.