Appleton-Century-Crofts, 1951
Buku Teks
Ferguson, Wallace K., author
Sir Isaac Pitman & Sons, [date of publication not identified]
Buku Teks
Ferguson, Wallace K.
Houghton Miffiln, 1942
Buku Klasik
Childe, V. Gordon, author
Routledge, 1996
Buku Teks
Schapiro, J. Salwyn
Houghton Miffiln, 1953
Buku Teks