Tipsaiyas, Tussanee, Pratak O-Prasertsawat, Vichai Vajrapreechaskul, and Kamheang Chaturachinda. 1990. “Perinatal Mortality of Singleton Pregnancy at Nakhon Pathom Hospital : 1984-1987”. Thai Journal of Obstetrics and Gynaecology 2 (1). Bangkok, Thailand:7-10. https://he02.tci-thaijo.org/index.php/tjog/article/view/257893.