Watcharachan Sukcharoenvipharat and  Prathuang Usaborisut and  Sirisak Choedkiatphon,  Comparative Study on Soil Tillage Using Rotary Tiller and Power Harrow.   journal   = {International Journal of Agricultural and Biosystems Engineering}, [online]. World Academy of Science, Engineering and Technology.
    September 2017, vol. 130(10). 744 - 747
    [viewed 10 December 2019]. Available from: https://publications.waset.org/pdf/10008098.