Kovavisarach, E., and T. Nalamlieng. “Perinatal Mortality in Rajavithi Hospital and Queen Sirikit National Institute of Child Health 1993-1997”. Thai Journal of Obstetrics and Gynaecology, vol. 12, no. 3, July 2000, pp. 195-9, https://he02.tci-thaijo.org/index.php/tjog/article/view/256785.