Hendy, H., S. Wandita, and I. M. Kardana. “Efficacy of Aminophylline Vs. Caffeine for Preventing Apnea of Prematurity”. Paediatrica Indonesiana, Vol. 54, no. 6, Dec. 2014, pp. 365-71, doi:10.14238/pi54.6.2014.365-71.