MLA

O'Brien, and Patrick Karl O'Brien. The Economies of Imperial China and Western Europe. Springer International Publishing, 2020.

APA

O'Brien, O., & O'Brien, P. Karl. (2020). The Economies of Imperial China and Western Europe. Springer International Publishing.

Chicago

O'Brien, and Patrick Karl O'Brien. The Economies of Imperial China and Western Europe. : Springer International Publishing, 2020.