Gaya APA

Longo, D, L., Kesper, D, L. (2011). Harrison's principles of internal medicine Vol. 1 (18th ed). New York: McGraw-Hill Information Services.

Gaya MLA

Longo, Dan, L.., Kesper, Dennis, L.. "Harrison's principles of internal medicine Vol. 1". 18th ed New York: McGraw-Hill Information Services, 2011. print.