Graham, A. J., Gelfand, G., McFadden, S. D., & Grondin, S. C. (2004). Levels of evidence and grades of recommendations in general thoracic surgery. Canadian Medical Association.
استشهاد بنمط شيكاغوGraham, Andrew J., Gary Gelfand, Sean D. McFadden, و Sean C. Grondin. Levels of Evidence and Grades of Recommendations in General Thoracic Surgery. Canadian Medical Association, 2004.
MLA استشهادGraham, Andrew J., Gary Gelfand, Sean D. McFadden, و Sean C. Grondin. Levels of Evidence and Grades of Recommendations in General Thoracic Surgery. Canadian Medical Association, 2004.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.