Surtinah, S. 2009. PEMBERIAN PUPUK ORGANIK SUPER NATURAL NUTRITION (SNN) PADA TANAMAN SELADA (Lactuca sativa, L) DI TANAH ULTISOL. Jurnal Ilmiah Pertanian. 6, 1 (Aug. 2009), 20-25. DOI:https://doi.org/10.31849/jip.v6i1.1291.