I am searching for a reference about the classification of algebraic surfaces over an arbitrary algebraically closed field of characteristic zero. In the 1949 book "le superficie algebriche" by Enriques there is no clear reference about the base field, as he only mentions some "ordinary space". Is it any arbitrary characteristic zero field, or $\mathbb{C}$? If it is $\mathbb{C}$, could you recommend a reference for the general zero characteristic case?