Putri Ana, Ayu, et al. “Prediksi Indeks Panen Jambu ‘Kristal’ Secara Non Destruktif Menggunakan Portable Near Infrared Spectrometer”. Jurnal Keteknikan Pertanian, vol. 9, no. 3, Dec. 2021, pp. 103-10, https://doi.org/10.19028/jtep.09.3.103-110.