Tang, J., X. Chen, and C. Sakondhavat. “Pulmonary Metastases in Gestational Trophoblastic Disease A Review of 223 Cases”. Thai Journal of Obstetrics and Gynaecology, vol. 1, no. 2, July 1989, pp. 97-100, https://he02.tci-thaijo.org/index.php/tjog/article/view/257903.