Yosmar, Siska, S Damayanti, and S Febrika. “LQ45 Stock Portfolio Selection Using Black-Litterman Model in Pandemic Time Covid-19”. Indonesian Journal of Statistics and Its Applications 5, no. 2 (June 30, 2021): 343–354. Accessed April 16, 2024. https://journal.stats.id/index.php/ijsa/article/view/823.