Chris A. Wozniak, editor
[, Springer], 2012
eBooks
Frederick A. Praeger, 1966
Buku Teks
Rand McNally, [date of publication not identified]
Buku Referensi
Petrides, George A., author
Houghton Mifflin, 1988
Buku Teks
Grolier Incorporated, 1964
Buku Referensi