Gaya APA

COTTON, P, B., WILLIAMS, C, B. (1990). Practical gastrointestinal endoscopy (3rd ed.). Oxford: Blackwell Scientific.

Gaya MLA

COTTON, Peter, B.., WILLIAMS, Chistopher, B.. "Practical gastrointestinal endoscopy". 3rd ed. Oxford: Blackwell Scientific, 1990. Buku.