Manonai , J., Wattanayingcharoenchai, R., & Chittacharoen, A. (1999). Sonographic Diagnosis of an Abdominal Pregnancy. Thai Journal of Obstetrics and Gynaecology, 11(2), 123–125. retrieved from https://he02.tci-thaijo.org/index.php/tjog/article/view/257172