Debalina Das, Susmita Bhattacharya, Parthasarathi Chakrabarty, Sipra Saha, and Nandita Pal, “A Retrospective Study on Pre Exposure Hydroxychloroquine and Ivermectin Prophylaxis for COVID-19 in Healthcare Workers in a Tertiary Care Hospital”, Int. J. Heal. Clin. Res., vol. 4, no. 17, pp. 66–70, Oct. 2021.