Natthawipa Onramai และ Porntip Phontusang and Anongnat Sriprachote. (2020) Spatial variability of extractable potassium in sandy-paddy soils in Northeast of Thailand: study of optimal distance between the sampling points. <i>Khon Kaen Agriculture Journal</i>, <i>48</i>(6), 1266-1275.Natthawipa Onramai และ Porntip Phontusang and Anongnat Sriprachote. "Spatial variability of extractable potassium in sandy-paddy soils in Northeast of Thailand: study of optimal distance between the sampling points". Khon Kaen Agriculture Journal 48 (2020):1266-1275.Natthawipa Onramai และ Porntip Phontusang and Anongnat Sriprachote. Spatial variability of extractable potassium in sandy-paddy soils in Northeast of Thailand: study of optimal distance between the sampling points. Faculty of Agriculture:ม.ป.ท. 2020.