Unpikool, A., C. Sareeborvornthanasak, and S. Sonbankoh. “Placental Sites and Preeclampsia in Singleton Pregnancy: A Retrospective Cohort Study”. The Clinical Academia, vol. 43, no. 2, June 2019, pp. 44-53, https://he02.tci-thaijo.org/index.php/theclinicalacademia/article/view/182144.