Citazione Stile APA (7a Edizione)

Rugg, H., & Krueger, L. (1938). Mankind throughout the ages. Ginn and Company.

Citazione stile Chigago Style (17a edizione)

Rugg, Harold, e Louise Krueger. Mankind Throughout the Ages. Boston: Ginn and Company, 1938.

Citatione MLA (9a ed.)

Rugg, Harold, e Louise Krueger. Mankind Throughout the Ages. Ginn and Company, 1938.