Cita APA (7th ed.)

Graebner, N. A. (1961). An uncertain tradition: American Secretaries of State in the twentieth century. McGraw-Hill.

Cita Chicago (17th ed.)

Graebner, Norman A. An Uncertain Tradition: American Secretaries of State in the Twentieth Century. New York: McGraw-Hill, 1961.

Cita MLA (8th ed.)

Graebner, Norman A. An Uncertain Tradition: American Secretaries of State in the Twentieth Century. McGraw-Hill, 1961.