Cambridge University Press, 2012
eBooks
Schwarzmantel, John
Sage, 2008
Buku Teks
Wetter, Gustav Andreas, 1911-, author
Frederick A. Praeger, 1962
Buku Teks
edited by Richard Freeborn and Jane Grayson
Macmillan, 1990
Buku Teks
Klein, Viola, author
Broadway House, 1946
Buku Teks