Roskin, Michael G.
Pearson/Prentice Hall, 2004
Buku Teks
Rourke, John T.
McGraw-Hill, 2010
Buku Teks
Andrew Hurrell, Ngaire Woods, Satria Utama S., Diana Arimbi
Fakultas Ekonomi UI, 2001
Buku Teks
Blackburn, Glenn
St. Martin's, 1985
Buku Teks
Rourke, John T.
McGraw-Hill, 2001
Buku Teks