Seth, Michael J., author
Littlefield, 2011
Buku Teks
Mott, George Fox
Barnes & Noble, Inc., 1957
Buku Teks
Hoyt, Robert S., author
Harcourt, Brace & World, 1957
Buku Teks
Myers, Alec Reginald, author
Penguin Books, 1952
Buku Teks
Melissa Calaresu; Danielle van den Heuvel.
Routledge, 2016
Buku Teks