1. Median episiotomies and complete perineal lacerations
2. A. M. Claye (1963 ): InBritish Obstetric and Gynaecological Practice , 3rd Edition , Heinemann, London, p. 893 .
3. S. G. Clayton, D. B. Fraser, and T. L. T. Lewis (1966 ): InObstetrics by Ten Teachers , 11th Edition . Edward Arnold, London, p. 550 .