Cita APA (7th ed.)

Ferguson, J. H., & McHenry, D. E. (1956). The american system of government (4a. ed.). McGraw-Hill.

Cita Chicago (17th ed.)

Ferguson, John H., i Dean E. McHenry. The American System of Government. 4a. ed. Nueva York: McGraw-Hill, 1956.

Cita MLA (9th ed.)

Ferguson, John H., i Dean E. McHenry. The American System of Government. 4a. ed. McGraw-Hill, 1956.