3Krageyim larsidag AY. Buyubayrak EE. Kars B. et al. Transvaginal sonography, sonohysterography, and hysteroscopy for investigation of focal intrauterine lesions in women with recurrent postmenopausalbleeding after dilatation & currettage [ J]. Arch Gyenecol Obstet, 2010,281(4 ) :637 - 643.