Cita APA (7th ed.)

Eibling, H. H., & Jackson, C. J. (1977). Two centuries of progress: United States history. Laidlaw brothers.

Cita Chicago (17th ed.)

Eibling, Harold H., i Carlton J. Jackson. Two Centuries of Progress: United States History. Irvine: Laidlaw brothers, 1977.

Cita MLA (9th ed.)

Eibling, Harold H., i Carlton J. Jackson. Two Centuries of Progress: United States History. Laidlaw brothers, 1977.