After Sales Service For Smartphone Iphone To Customer Loyalty. APTISI Transactions on Management, [S. l.], v. 5, n. 1, p. 62–72, 2021. DOI: 10.33050/atm.v5i1.1436. Disponível em: https://www.ijc.ilearning.co/index.php/ATM/article/view/1436. Acesso em: 4 oct. 2025.