Yusnaini, Sri, Ainin Niswati, Mas Achmad Syamsul Arif, and Masanori Nonaka. 2008. “The Changes of Earthworm Population and Chemical Properties of Tropical Soils under Different Land Use Systems”. JOURNAL OF TROPICAL SOILS 13 (2):131-37. https://doi.org/10.5400/jts.2008.v13i2.131-137.