Most research on the Hasse-Weil zeta function focuses on some particular type of algebraic variety, and general surveys usually deal mostly with the better understood elliptic curve case. I am looking for references about the HW zeta for arbitrary variety and number field, particularly analytic continuation and functional equation (this is, not focused on special values or zeroes). Also, I have Serre's "Facteurs locaux", so probably anything published before 1970 would be redundant.