Khedkar, I., D. Prasad, and A. Datta. “Diagnostic Value of Upper Gastrointestinal Endoscopy Prior to Elective Laparoscopic Cholecystectomy for Symptomatic Cholelithiasis”. International Surgery Journal, vol. 5, no. 1, Dec. 2017, pp. 105-9, doi:10.18203/2349-2902.isj20175549.