Gaya APA

Greenberger, N, J. (2009). Current Diagnosis Treatment: Gastroentrrology, Hepatology Endoscopy . America: Mc Graw Hill.

Gaya MLA

Greenberger, Norton, J.. "Current Diagnosis Treatment: Gastroentrrology, Hepatology Endoscopy". America: Mc Graw Hill, 2009. Text.