“Is Narcissism Really the Secret to Sales Success? Unraveling The Role of Effort in Salesperson Outcomes”. Psikostudia : Jurnal Psikologi 15, no. 3 (September 6, 2026): 677–688. Accessed November 5, 2026. https://e-journals.unmul.ac.id/index.php/PSIKO/article/view/28896.