Clemens, S. L. (1960). Clemens, Samuel L.; Howells, William D.; Smith, Henry Nash; Gibson, William M: Mark Twain-Howells Letters. Volume II. Harvard University Press. https://doi.org/10.4159/harvard.9780674368873
Chicago Style (17th ed.) CitationClemens, Samuel L. Clemens, Samuel L.; Howells, William D.; Smith, Henry Nash; Gibson, William M: Mark Twain-Howells Letters. Volume II. Cambridge, Mass: Harvard University Press, 1960. https://doi.org/10.4159/harvard.9780674368873.
MLA (9th ed.) CitationClemens, Samuel L. Clemens, Samuel L.; Howells, William D.; Smith, Henry Nash; Gibson, William M: Mark Twain-Howells Letters. Volume II. Harvard University Press, 1960. https://doi.org/10.4159/harvard.9780674368873.
Warning: These citations may not always be 100% accurate.