edited by Sarah Gehlert; Teri Arthur Browne
John Wiley & Sons, 2012
Buku Teks
Hess, Hartmut
International Friedrich-Erbert-Stftung (FES), 2006
Buku Teks
Skidmore, Rex A. (Rex Austin)
Prentice Hall International, 1991
Buku Teks
Ferguson, Elizabeth A.
J.B. Lippincott, 1975
Buku Teks
Skidmore, Rex A. (Rex Austin)
Prentice Hall International, 1991
Buku Teks