Susana, Fera, Didik Eko Julianto, & Suhartono Suhartono. " The Influence of Price and Promotion on Consumer Purchase Decisions at Sumber Makmur Kopi Jember." Electronical Journal of Social and Political Sciences (E-SOSPOL) [Online], 10.1 (2023): 79-88. Web. 5 Jul. 2024