Spate, Oskar Hermann Kristian
Australia, New Zealand and the Pacific
Oxford University Press, 1965
 Buku Teks
Grant, Douglas
Mark Twain
Grove Press, 1962
 Buku Teks
The Autobigraphy of Mark Twain
NY. Harper & Brothers
 Buku Teks
Mark Twain letters to mary
edited with a commerntary by Lewis G. Leary
Columbia University Press, 1961
 Buku Teks
Smith, Henry Nash
Mark Twain: the development of a writer
Belknap Press of Harvard University Press, 1967
 Buku Teks