Cita APA (7th ed.)

Freidel, F. (1982). America in the twentieth century (5th ed.). Knopf : distributed by Random House, McGraw-Hill.

Cita Chicago (17th ed.)

Freidel, Frank. America in the Twentieth Century. 5th ed. New York: Knopf : distributed by Random House, McGraw-Hill, 1982.

Cita MLA (8th ed.)

Freidel, Frank. America in the Twentieth Century. 5th ed. Knopf : distributed by Random House, McGraw-Hill, 1982.