by Franz Michael, Carl Linden, Jan Pryblyla, Jurgen Domes
Westview Press, 1990
Buku Referensi
Enrich Professional Pub., 2012
Buku Teks
Bertram, James M.
Macmillan, 1937
Buku Teks
University of Chicago, [1968]
Buku Teks
Wang, Wensheng, 1976-, author
Harvard University Press, 2014
Buku Teks