Puangsricharern, A., & Chaonoum, W. (2012). Trends of Forceps and Vacuum Deliveries in Rajavithi Hospital from 2002 to 2009. Thai Journal of Obstetrics and Gynaecology, 20(4), 198–208. retrieved from https://he02.tci-thaijo.org/index.php/tjog/article/view/4689