Yenfrida Silitonga, Nurhayati, and Muhammad Rizwan, “QUALITY STUDY OF ARABICA COFFEE COMMODITY (Coffea arabica L.) BASED ON SNI COFFEE BEANS No. 01-2907-2008 REVIEWED FROM THE ASPECT OF GOOD AGRICULTURAL PRACTICES (GAP) IN SIMALUNGUN REGENCY”, IJEBAS, vol. 5, no. 3, pp. 1383–1389, Jun. 2025.