Yudha, A. “A Source Effect Theory Perspective on How Opinion Leadership, Parasocial Relationship, and Credibility Influencers Affect Purchase Intention”. Journal of Theory and Applied Management (Jurnal Manajemen Teori Dan Terapan), vol. 16, no. 2, Aug. 2023, pp. 240-53, doi:10.20473/jmtt.v16i2.48099.