PUTRA, N. P. P.; LISTYOKO, A. S.; CHRISTANTO, A. PaO2, SaO2, and PaO2/FiO2 Ratio as A Predictor Disease Severity in Hospitalized COVID-19 Patients. Journal Of The Indonesian Medical Association, v. 70, n. 12, p. 253-259, 21 Jan. 2021.