Musfardi Rustam, Martha Hasanah Rustam, Afrinaldy Rustam, Yepi Kurniadi, Imam Slamet Prasetio, and Umi Nadatul Annisa, “Characteristics and comorbidity of confirmed COVID-19 death cases at the Arifin Achmad Hospital in Riau province from March 2020 to September 2021”, J Pak Med Assoc, vol. 74, no. 5 (Supple), pp. S18-S20, Jun. 2024.