PanjaitanA.; AnasI.; WidyastutiR.; WidayatiW. E. Ability of Endophytic Diazotrophic Bacteria in Stimulating Growth of Oil Palm Seedlings (Elaeis guineensis Jacq). Jurnal Ilmu Tanah dan Lingkungan, v. 17, n. 1, p. 1-7, 1 Apr. 2015.