C. Suchartwatnachai, U. Theppisai, S. Preutthipan, M. Jirapinyo, C. Thanuntaseth, and A. Chittacharoen, “Endometrial Thickness in Asymptomatic Postmenopausal Women ”, Thai J Obstet Gynaecol, vol. 9, no. 3, pp. 219–223, Sep. 1997.