Mubandari, Gayatri Putri, and Sri Hartini. “VALUE PROPOSITION ANALYSIS TELKOMSEL LOOP CARD PRODUCTS”. Jurnal Ekonomi 12, no. 02 (April 20, 2023): 1036–1040. Accessed December 5, 2024. https://ejournal.seaninstitute.or.id/index.php/Ekonomi/article/view/1839.