Brown, Joe David
Time Incorporated, 1961
Buku Teks SO
Hobbs, Lisa
McGraw-Hill, 1967
Buku Teks SO
Spear, Percival
The University of Michigan Press, 1961
Buku Teks
Ministry of Information, 1950
Buku Teks SO
The Publications Division Ministry of Information & Broadcasting Goverment of India , 1953
Buku Teks SO