Kuswanto, K., R. Refnida, and L. Ratnadillah. “The Effect of Product Perception and Price Perception on Reference Book Purchase Decisions ”. Jurnal Pendidikan Ekonomi Dan Bisnis (JPEB), Vol. 9, no. 2, Oct. 2021, pp. 179-88, doi:10.21009/JPEB.009.2.8.