MLA

Qi, Xingshun, and Weifen Xie. Portal Vein Thrombosis. Springer, 2021.

APA

Qi, X., & Xie, W. (2021). Portal Vein Thrombosis. Springer.

Chicago

Qi, Xingshun, and Weifen Xie. Portal Vein Thrombosis. : Springer, 2021.