Lynton, Rolf P.
Carolina Population Center, University of North Carolina , 1974
Buku Teks
Lane, Mary Turner
Carolina Population Center, 1974
Buku Teks
edited by Jane A. Menken, Ann K. Blanc, Cynthia B. Lloyd
The population council, 2002
Buku Teks
by W. D. Borrie [and others]
UNESCO, 1957
Buku Teks
The Unesco Press, 1975
Buku Teks