Gunawan, Antoni, and Tina Melinda. “Analysis of Marketing Mix and Purchasing Decisions (a Study of Kene Kopi Products)”. KnE Social Sciences 5, no. 5 (March 22, 2021): 510–518. Accessed April 20, 2024. https://knepublishing.com/index.php/KnE-Social/article/view/8838.