Authors: Pirhonen, JP Grenman, SE Haadem, K Gudmundsson, S Lindqvist, P Siihola, S Erkkola, RU Marsal, K

Citation: Jp. Pirhonen et al., Frequency of anal sphincter rupture at delivery in Sweden and Finland - result of difference in manual help to the baby's head, ACT OBST SC, 77(10), 1998, pp. 974-977