ProQuest (Firm), Burlingame, M., Hay, J., & Nicolay, J. G. (2007). Abraham Lincoln: The observations of John G. Nicolay and John Hay. Southern Illinois University Press.
Chicago Style (17th ed.) CitationProQuest (Firm), Michael Burlingame, John Hay, and John G. Nicolay. Abraham Lincoln: The Observations of John G. Nicolay and John Hay. Carbondale: Southern Illinois University Press, 2007.
MLA (9th ed.) CitationProQuest (Firm), et al. Abraham Lincoln: The Observations of John G. Nicolay and John Hay. Southern Illinois University Press, 2007.
Warning: These citations may not always be 100% accurate.