Brown, A.J., author
George Allen and Unwin, 1959
Buku Teks
Brown, A.J., author
George Allen and Unwin, 1959
Buku Klasik
Case, Karl E., author
Pearson, Prentice Hall, 2009
Buku Teks
Mankiw, N. Gregory, author
Harcout College, 1998
Buku Teks
Case, Karl E., author
Prentice-Hall, 2004
Buku Teks