Ewen, David
The world of twentieth-century music
Prentice Hall, 1968
 Buku Referensi
Thwaite, Anthony
Twentieth-century English poetry : an introduction
Heineman, 1984
 Buku Teks
Proctor, George A.
Canadian music of the twentieth century / George Alfred Proctor
University of Toronto Press, 1980
 Buku Teks
Revolutions of the late twentieth century
edited by Jack A. Goldstone, Ted Robert Gurr, Farrokh Moshiri
Westview Press, 1991
 Buku Teks
Varga, Eugen, 1879-1964
Twentieth century capitalism
Foreign Languages Publishing House, 1961
 Buku Teks