Sunsaneevithayakul, P., T. Siwadune, D. Boriboonhirunsarn, V. Titapant, and A. Sutanthavibul. “Reference Centile Charts for Fetal Umbilical Artery Doppler Velocimetry Waveform of Thai Fetuses”. Thai Journal of Obstetrics and Gynaecology, vol. 12, no. 3, July 2000, pp. 201-1, https://he02.tci-thaijo.org/index.php/tjog/article/view/256789.