APA (7th ed.) Citation

Lincoln, A., Tracy, G. A., & Allen, F. H. (1917). Uncollected letters of Abraham Lincoln. Houghton Mifflin Company.

Chicago Style (17th ed.) Citation

Lincoln, Abraham, Gilbert A. Tracy, and Francis H. Allen. Uncollected Letters of Abraham Lincoln. Boston, New York: Houghton Mifflin Company, 1917.

MLA (8th ed.) Citation

Lincoln, Abraham, et al. Uncollected Letters of Abraham Lincoln. Houghton Mifflin Company, 1917.