Kelly, Marce, author
Cengage Learning, 2016
Buku Teks
Kroenke, David M., 1946-, author
Mitchell Publishing, 1987
Buku Teks
Wilson, Graham K., author
Chatham House, 1985
Buku Teks
O`Brien, James A., 1936-, author
Richard D. Irwin, 1975
Buku Teks
Fuori, William M., author
Prentice-Hall, 1981
Buku Teks