Paryanti, A. B., and S. Sumarsid. “Analysis The Quality Of Service And Effectiveness E-Commerce Auy Publisher Using The Method E-Servqual”. Agregat: Jurnal Ekonomi Dan Bisnis, vol. 3, no. 1, Mar. 2019, pp. 25-34, https://journal.uhamka.ac.id/index.php/agregat/article/view/3327.