• Andrews V, Sultan AH, Thakar R, Jones PW. Occult anal sphincter injuries--myth or
  reality? BJOG. 2006;113(2):195-200.
• Edqvist M, Hildingsson I, Mollberg M, Lundgren I, Lindgren H. Midwives' Management
  during the Second Stage of Labor in Relation to Second-Degree Tears-An Experimental
  Study. Birth. 2017;44(1):86-94.
• Huber M, Larsson C, Lehmann JP, Strigård K, Lindam A, Tunón K. Sonographic
  postpartum anal sphincter defects and the association with pelvic floor pain and
  dyspareunia. Acta Obstet Gynecol Scand. 2023;102(10):1290-7.
• SBU Statens beredning för medicinsk och social utvärdering AfHTA, of Social Services.
  Diagnostik samt erfarenheter av bemötande och information. 2021-03-01;SBU-rapport nr
  323.