Anusasananant, K., S. Armarttasn, and B. Wiriyasirivaj. “The Association between Antenatal Umbilical Cord Coiling Index Pattern and Meconium-stained Amniotic Fluid in Gestational Diabetic Mellitus”. Thai Journal of Obstetrics and Gynaecology, vol. 22, no. 2, Apr. 2014, pp. 67-73, https://he02.tci-thaijo.org/index.php/tjog/article/view/12496.