Berlin, Isaiah
The Roots of romanticism
Princeton University Press, 2001
 Buku Teks
Rose, Arnold M.
The roots of prejudice
UNESCO, 1951
 Buku Teks
America
New York: W.W.Norton & Company, 1988,
 Buku Referensi
Cho, Hae-il
America
Dong-su-Munhak-sa, 1990
 Buku Teks
India's roots of democracy
Carl C. Taylor ... [and others]
Orient Longmans, 1965
 Buku Teks