Cita APA (7a ed.)

SpringerLink (Online service), Porro, G. B., & Maconi, G. (2007). Ultrasound of the gastrointestinal tract. Springer-Verlag Berlin Heidelberg.

Cita Chicago Style (17a ed.)

SpringerLink (Online service), Gabriele Bianchi Porro, y Giovanni Maconi. Ultrasound of the Gastrointestinal Tract. Berlin, Heidelberg: Springer-Verlag Berlin Heidelberg, 2007.

Cita MLA (8a ed.)

SpringerLink (Online service), et al. Ultrasound of the Gastrointestinal Tract. Springer-Verlag Berlin Heidelberg, 2007.