DeVane, William Clyde
Higher education in twentieth-century America
Harvard University Press, 1965
 Buku Teks
Schapiro, J. Salwyn [Jacob Salwyn], 1879-1973
The world in crisis : political and social movement in the twentieth century
McGraw-Hill, 1950
 Buku Teks
Simai, Mihály
Global power structure, technology and world economy in the late twentieth century
Pinter Publishers , 1990
 Buku Teks SO
Woodham, Jonatham M.
Twentieth-Century design
Oxford University Press, 1997
 Buku Teks SO
Chant, Christopher
Twentieth century war machines
London: Chancellor Press, 1999,
 Buku Referensi