Hurskainen R, Teperi J, Aalto AM, Grenman S, Kivelä A, Kujansuu E, Vuorma S, Yliskoski M, Rissanen P, Paavonen J. Levonorgestrel-releasing intrauterine system or hysterectomy in the treatment of essential menorrhagia: predictors of outcome. Acta Obstet Gynecol Scand. 2004 Apr;83(4):401–3. doi: 10.1111/j.0001-6349.2004.00440.x. PMID: 15005790.