S. C, N. A, Ireddy VK, Patil VK, Prabhu R. Efficacy of closed internal sphincterotomy using von grafae knife in the management of chronic anal fissures. Int Surg J [Internet]. 2017 Apr. 22 [cited 2025 Nov. 10];4(5):1532-5. Available from: https://www.ijsurgery.com/index.php/isj/article/view/1292