MLA

Gazouli, and George E Theodoropoulos. Digestive System Diseases. Springer International Publishing, 2019.

APA

Gazouli, G., & Theodoropoulos, G. E. (2019). Digestive System Diseases. Springer International Publishing.

Chicago

Gazouli, and George E Theodoropoulos. Digestive System Diseases. : Springer International Publishing, 2019.