Ashford, Lori S., author
Population Reference Bureau, 2004
Buku Teks
Higgins, David, author
Prentice-Hall, 1983
Buku Teks
HPAA, 1984
Buku Teks
Kettner, Peter M, author
SAGE, 2017
Buku Teks
Abramson, J. H. (Joseph Herbert), 1924-, author
Oxford University Press, 1983
Buku Teks