Albayati, Rasha Kadim, et al. “Topical Combination of Nifedipine With Lidocaine Is a Promising Medical Treatment for Anal Fissure”. Diyala Journal of Medicine, vol. 15, no. 2, Dec. 2018, pp. 98-103, https://djm.uodiyala.edu.iq/index.php/djm/article/view/185.