N. El Maidah and C. Dwi Suhendra, “Enhanced Efficiency of Coffee Fruit Ripe Sorting System through Ultrasound-based Optimization and Fuzzy Logic: Peningkatan Efisiensi Sistem Sortasi Matang Buah Kopi melalui Optimasi Berbasis Ultrasound dan Logika Fuzzy”, JISTECH, vol. 12, no. 1, pp. 175-179, Jun. 2023.