Gaya APA

Haubrich, J, E, B, W, S. (1991). Gastrointestinal symptom: clinical interpretations . Philadelphia: B. C. Decker Inc..

Gaya MLA

Haubrich, J., Edward, Berk,, William, S.. "Gastrointestinal symptom: clinical interpretations". Philadelphia: B. C. Decker Inc., 1991. Text.