Halwa Annisa Khoiri, and Wildanul Isnaini. “Analisis Pengaruh Covid-19 Dan Pembatasan Sosial Berskala Besar (PSBB) Terhadap Fluktuasi IHSG”. Limits: Journal of Mathematics and Its Applications, vol. 19, no. 1, May 2022, pp. 1-13, https://journal.its.ac.id/index.php/limits/article/view/5329.