SIAHAAN, S. I., and Poniman. “ANAYSIS OF FACTORS AFFECTING PROFITABILITY IN MANUFACTURING COMPANIES LISTED ON THE INDONESIA STOCK EXCHANGE ”. Jurnal Mantik, vol. 6, no. 2, July 2022, pp. 1584-93, https://iocscience.org/ejournal/index.php/mantik/article/view/2573.