RADULOVA, P.; SLANCHEVA, B.; MARINOV, R. Oxygenation Index – an Objective Indicator of the Severity and Treatment Effect of Persistent Pulmonary Hypertension of the Newborn. Proceedings of the Bulgarian Academy of Sciences, Sofia, Bulgaria, v. 76, n. 3, p. 440–447, 2023. DOI: 10.7546/CRABS.2023.03.13. Disponível em: https://www.proceedings.bas.bg/index.php/cr/article/view/278. Acesso em: 25 oct. 2026.