Utami, Eristy M., et al. “THE DIFFERENCES IN STOCK PORTFOLIO PERFORMANCE BEFORE AND DURING THE COVID-19 PANDEMIC: STUDY ON THE LQ-45 INDEX AND THE JAKARTA ISLAMIC INDEX”. CENTRAL ASIA AND THE CAUCASUS, vol. 23, no. 1, Jan. 2022, pp. 4487-96, https://ca-c.org/index.php/cac/article/view/442.