Zulqarnain A, Hussain M, Suleri KM, Ali Ch. Z. Comparison of Caffeine versus Theophylline for apnea of prematurity: Caffeine vs. Theophylline for apnea of prematurity. Pak J Med Sci [Internet]. 2019Jan.22 [cited 2024Apr.19];35(1). Available from: https://www.pjms.org.pk/index.php/pjms/article/view/94