Sholichah H, Johan S. The Effect of First Case Covid-19 Announcement on Average Trading Volume Activity of Pharmaceutical Sector Companies. J. Manaj. Bisnis dan Kewirausahaan [Internet]. 2022 Mar. 29 [cited 2025 Feb. 15];6(2):218-24. Available from: https://journal.untar.ac.id/index.php/jmbk/article/view/11673