Chambers 20th century dictionary
edited by E.M. Kirkpatrick ; assistant editors, C.M. Schwarz ... [and others]
Chambers, 1983
 Buku Referensi
Carlson, Paul A.
20th century bookkeeping & accounting
South Western, 1957
 Buku Teks
Icons of architecture : the 20th century
edited by Sabine Thiel-Siling ; with contributions by Wolfgang Bachmann ... [and others]
Preste, 1998
 Buku Teks SO
Freud and the 20th century
edited and selected by Benjamin Nelson
George Allen and Unwin, 1958
 Buku Teks SO
Berle, Adolf A., Jr.
The 20th century capitalist revolution
Harcourt, Brace, 1954
 Buku Klasik