Ervani, N., Lubis, B., Azlin, E., Tjipta, G., & Emsyah, L. (2009). Comparison of the effect of oral multiple dose with single intramuscular vitamin K1 administration on prothrombin time in term baby. Paediatrica Indonesiana, 49(5), 281-5. https://doi.org/10.14238/pi49.5.2009.281-5