Nur Ikhsan Umam, N. Nasib, Debora Tambunan, Ahmad Rivai, and Zulia Rifda Daulay, “Asistensi Triggers for Decreasing Coffee Purchase Decisions Caused by the Inability of Different Packaging Designs, Narrow Parking Area And Slow In Responding To Complaints”, Mantik, vol. 5, no. 4, pp. 2492-2499, Feb. 2022.