Usmar, Dani. “Transformasi PPKM Terhadap Abnormal Return Sub Industri Farmasi”. Jurnal Sosial Teknologi 1, no. 11 (November 15, 2021): 1.341 – 1.352. Accessed February 1, 2026. https://sostech.greenvest.co.id/index.php/sostech/article/view/233.