GPS

MLA

Xu, Guochang; Xu, Yan, and Yan Xu. Gps. Springer Berlin Heidelberg, 2016.

APA

Xu, Y.Xu, Y. (2016). GPS. Springer Berlin Heidelberg.

Chicago

Xu, Guochang; Xu, Yan, and Yan Xu. GPS. : Springer Berlin Heidelberg, 2016.