Erwanto, Engga L. “Effect of Spontaneous Delivery and Elective Caesarean Section on Number of Bifidobacterium Colony in Newborns”. Indonesian Journal of Obstetrics and Gynecology 35, no. 2 (December 16, 2016). Accessed February 21, 2026. https://www.inajog.com/index.php/journal/article/view/222.