Utami, Kartika, et al. “The Kinetics Curve of Nitrogen Mineralization from Perennial Leaves Litter Decomposed by Earthworm (Phretima Californica)”. SAINS TANAH - Journal of Soil Science and Agroclimatology, vol. 17, no. 2, Dec. 2020, pp. 152-60, https://doi.org/10.20961/stjssa.v17i2.46928.