Artikel Jurnal
edited by Clark Tibbitts and Wilma Donahue
Prentice-Hall, 1960
Buku Teks
by Yoichi Okazaki [and others]
Foreign Press Center, 1990
Buku Teks
Hillier, Susan, author
Wadsworth and Cengage Learning, 2011
Buku Teks
edited by John Field, Ronald J. Burke and Cary L. Cooper.
SAGE, 2013
Buku Referensi