Van Caspel, Venita
ian Xia Wen Hua, 1990
Buku Teks
Rosefsky, Robert S., author
John Wiley & Sons, 1978
Buku Teks
Stillman, Richard J., author
Prentice-Hall, 1972
Buku Teks
Zimmerman, Gary, author
John Wiley & Sons, 1980
Buku Teks
Richards, R. Malcolm, author
Scott, Foresman, 1984
Buku Teks