Respita, Intan Annisa, et al. “Correlation of Leaf NPK and Leaf Pigments of Coleus Atropurpureus L. Benth During Vegetative and Generative Phases”. Journal of Tropical Crop Science, vol. 6, no. 03, Oct. 2019, pp. 174-81, doi:10.29244/jtcs.6.03.174-181.