Gulzar, J. S., S. B. Paruthy, and S. V. Arya. “Improving Outcome in Perforated Peptic Ulcer Emergency Surgery by Boey Scoring”. International Surgery Journal, vol. 3, no. 4, Dec. 2016, pp. 2120-8, doi:10.18203/2349-2902.isj20163585.