Asraf H, Muhammad, Nooritawati Md Tahir, Nur Dalila K.A., and Aini Hussain. 2018. “An Agricultural Tele-Monitoring Method in Detecting Nutrient Deficiencies of Oil Palm Leaf”. International Journal of Engineering and Technology 7 (4.11): 227-30. https://doi.org/10.14419/ijet.v7i4.11.20812.