Nurjaya, . and Nursyamsi, D. (2013) “Effectiveness of Direct Application of Phosphate Rock in Upland Acid Inceptisols Soils on Available-P and Maize Yield”, JOURNAL OF TROPICAL SOILS, 18(1), pp. 1–9. doi: 10.5400/jts.2013.v18i1.1-9.