Kuncoro, Amin, Iwan Suwarso, Ratih Hesty P, and Iwan Gunawan. “Loyalitas Konsumen: (Relationship Marketing Herbalife Semarang)”. Jurnal Bingkai Ekonomi (JBE) 6, no. 1 (February 8, 2021): 72-83. Accessed January 22, 2025. https://itbsemarang.ac.id/sijies/index.php/jbe33/article/view/103.