Citazione Stile APA (7a Edizione)

Duffy, D., & Frey, M. (1979). Directory of African and Afro-American studies in the United States (6th. ed.). Crossroads Press.

Citazione stile Chigago Style (17a edizione)

Duffy, David, e Mitsue Frey. Directory of African and Afro-American Studies in the United States. 6th. ed. [Waltham, Mass?]: Crossroads Press, 1979.

Citatione MLA (8a ed.)

Duffy, David, e Mitsue Frey. Directory of African and Afro-American Studies in the United States. 6th. ed. Crossroads Press, 1979.