Ross, R. S., & study guide by Donald C.William. (1996). American national government: Institutions, policy and participation. McGraw-Hill.
Cita Chicago (17th ed.)Ross, Robert S., i study guide by Donald C.William. American National Government: Institutions, Policy and Participation. New York: McGraw-Hill, 1996.
Cita MLA (9th ed.)Ross, Robert S., i study guide by Donald C.William. American National Government: Institutions, Policy and Participation. McGraw-Hill, 1996.
Atenció: Aquestes cites poden no estar 100% correctes.