Guðný B. Akralíð,Luit  Penninga,Morten  Thorsteinsson,Sidsel G. Møller,
Gallstone ileus: a seldom cause of mechanical bowel obstruction
Surgical Case Reports
2018
2613-5965
http://dx.doi.org/10.31487/j.SCR.2018.10.009
https://www.sciencerepository.org/gallstone-ileus-a-seldom-cause-of-mechanical-bowel-obstruction-1-109 
Abstract: Keywords: Gallstone ileus, fistula