American Gastroenterological Association. (2004). Gastroenterology. W.B. Saunders.
Citação do estilo Chicago (17ª ed.)American Gastroenterological Association. Gastroenterology. Philadelphia, Pa: W.B. Saunders, 2004.
Citação MLA (8ª ed.)American Gastroenterological Association. Gastroenterology. W.B. Saunders, 2004.
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