Cita APA (7a ed.)
Unger, I., & Unger, D. (1995). These United States: The questions of our past (6th, combined ed.). Prentice Hall.
Cita Chicago Style (17a ed.)
Unger, Irwin, y Debi Unger. These United States: The Questions of Our Past. 6th, combined ed. Englewood Cliffs, N.J.: Prentice Hall, 1995.
Cita MLA (9a ed.)
Unger, Irwin, y Debi Unger. These United States: The Questions of Our Past. 6th, combined ed. Prentice Hall, 1995.
Precaución: Estas citas no son 100% exactas.