Παραπομπή APA

Koval, J. M. (1967). Michigan's future: Its population and its economy. [s.l.]: [s.n.].

Παραπομπή Chicago Style

Koval, John M. Michigan's Future: Its Population and Its Economy. [s.l.]: [s.n.], 1967.

Παραπομπή MLA

Koval, John M. Michigan's Future: Its Population and Its Economy. [s.l.]: [s.n.], 1967.

Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.