Raksun, Ahmad, et al. “Vegetative Growth of Kale Land (Ipomoea Reptans poir.) Due to Different Doses of NPK and Bokashi Fertilizer”. Jurnal Biologi Tropis, vol. 20, no. 2, Aug. 2020, pp. 305-13, doi:10.29303/jbt.v20i2.2022.