Vogel JD, Johnson EK, Morris AM, et al. Clinical Practice Guideline for the Management of Anorectal Abscess, Fistula-in-ano, and Rectovaginal Fistula. Dis Colon Rectum 2016; 59(12):1117–33 Gastrointestinal medicine.
https://www.bupa.co.uk/health-information/digestive-gut-health/anal-fistula-surgery