RESEARCH ARTICLE Vol. 22 (3) December 2010, p. 869-877 EFFECTS OF N, P AND K FERTILIZERS ON LEAF TRACE ELEMENT LEVELS OF OIL PALM IN SUMATRA TOHIRUDDIN, L* ; TANDIONO, J* ; SILALAHI, Abner J* ; PRABOWO, N.E.* ; FOSTER, H.L* FULL TEXT | DOWNLOAD PDF