Swift, Jeremy
The Sahara
Time-Life Internationa, 1975
Buku Teks SO
Kagan, Robert A.
Philippe nonet phlip sedenick
Buku Teks
Price, Willard
Underwater adventure
John Day, 1954
Buku Teks SO
Stafford, J.
Boston Adventure
New York Harcourt, Brace and Company 1944
Buku Teks
A Symposium on fertility in sub-sahara Africa
Washington, D.C :Worl bank, 1996.,
Buku Teks