Clinical guidelines for the management of gastrointestinal fistula – developed by experts of the Polish Surgical Society. - Sobocki, Jacek; Jackowski, Marek; Dziki, Adam; Tarnowski, Wiesław; Banasiewicz, Tomasz; Kunecki, Marek; Słodkowski, Maciej; Stanisławski, Michał; Zaczek, Zuzanna; Richter, Piotr; Matyja, Andrzej; Frączek, Mariusz; et al. (Polish Journal of Surgery, 2021)