Ashwin Porwal, Paresh Gandhi, Deepak Kulkarni 2018, 'A novel four quadrant laser sphincterotomy for idiopathic severe anal stenosis', Journal of Coloproctologyhttp://www.sciencedirect.com/science/article/pii/S2237936317301065. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)