Yulia, M., A. R. Asnaning, and D. Suhandy. “The Influence of Particle Size of Ground Roasted Coffee in Discrimination of Decaffeinated Coffee Using Ultraviolet-Visible Spectroscopy and PLS-DA Method”. Jurnal Penelitian Pertanian Terapan, vol. 18, no. 1, Jan. 2018, pp. 46-51, doi:10.25181/jppt.v18i1.1226.