Gaya APA

wyllie, R., hyams, J, S. (2007). pediatric gastrointestinal and liver disease (Ed.4). USA: Saunders Elsevier.

Gaya MLA

wyllie, Robert., hyams, Jeffrey, S. "pediatric gastrointestinal and liver disease". Ed.4 USA: Saunders Elsevier, 2007. Text.