Coulmas, Florian, author
Cambridge University Press, 2005
Buku Teks
Stewart, Rosemary, author
McGraw-Hill, 1976
Buku Teks
Hogbin, Herbert Ian, author
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Buku Teks
Stewart, Rosemary, author
Prentice-Hall, 1982
Buku Teks
United Nations Population Fund
UNFPA, 1994
Buku Teks