Arshad, M.S., Adnan, M., Anwar-ul-Haq, H.M. and Zulqarnain, A. 2021. Postnatal causes and severity of persistent pulmonary Hypertension of Newborn. Pakistan Journal of Medical Sciences. 37, 5 (Jul. 2021). DOI:https://doi.org/10.12669/pjms.37.5.2218.