edited by William Marshall, Chuck Alston and Tom Mirga
Rowman & Littlefield, 1997
Buku Teks
Nasional Geographic, 2009
Buku Teks
Warner, W. Lloyd, author
Harper & Brothers , 1955
Buku Teks
edited by Carroll W. Pursell
MIT Press, 1981
Buku Teks
Will Buckingham, Douglas Burnham, Clive Hill, Peter J. King, John Marenbon, Marcus Weeks
DK Pub, 2011
Buku Teks