1. Verrucous squamous carcinoma as a complication of recurrent multiple perianal fistulae;Kyzer, S.; Bayer, I.; Turani, H.; Chaimoff, C.;Colo-proctology
2. Relation of fistula-in-ano to cancer of the anal;Rossner, C.
3. Carcinoma associated with fistula-in-ano;Kline, R.J.; Spencer, R.J.; Harrson, E.G.;Arch Surg