Chicago: Mark Twain, "Foreword," Mark Twain’s Letters— Volume 1 (1835-1866), ed. Paine, Albert Bigelow, 1861-1937 and trans. Townsend, R.S. in Mark Twain’s Letters—Volume 1 (1835-1866) (New York: A. L. Burt Company, 1916), Original Sources, accessed November 21, 2024, http://originalsources.com/Document.aspx?DocID=32S7T4N8MSDQE4R.
MLA: Twain, Mark. "Foreword." Mark Twain’s Letters— Volume 1 (1835-1866), edited by Paine, Albert Bigelow, 1861-1937, and translated by Townsend, R.S., in Mark Twain’s Letters—Volume 1 (1835-1866), Vol. 22, New York, A. L. Burt Company, 1916, Original Sources. 21 Nov. 2024. http://originalsources.com/Document.aspx?DocID=32S7T4N8MSDQE4R.
Harvard: Twain, M, 'Foreword' in Mark Twain’s Letters— Volume 1 (1835-1866), ed. and trans. . cited in 1916, Mark Twain’s Letters—Volume 1 (1835-1866), A. L. Burt Company, New York. Original Sources, retrieved 21 November 2024, from http://originalsources.com/Document.aspx?DocID=32S7T4N8MSDQE4R.