Israel, Saul
World geography today
Holt, Rinehart and Winston, 1976
Buku Teks SO
Federico, Ronald C.
Social welfare today's world
McGraw-Hill, 1990
Buku Teks
Talbot
South Asia In The World Today
Buku Teks
Berger, Morroe
The Arab world today
Anchor Books, 1964
Buku Teks SO
Stair, Ralph M., Jr.
Computers in today's world
Irwin, 1986
Buku Teks SO