Pick, James B.
Westview , 1989
Buku Referensi
Donnelly, Thomas C.
The University of New mexico Press, 1953
Buku Teks
Vaillant, George C.
Penguin Books, 1944
Buku Teks SO
Grayson, George W.
Thomson, 2004
Buku Teks SO
Yampolsky, Mariana, 1925-2002
Thames and Hudson, 1993
Buku Teks SO