Dulles, Foster Rhea
Twentieth century America
Houghton-Mifflin, 1945
 Buku Teks SO
Braeman, John
American politics in the twentieth century
Thomas Y. Crowill, 1969
 Buku Teks SO
Margolies, Edward
Native sons : a critical study of twentieth-century Negro American authors
J.B. Lippincott, 1969
 Buku Teks SO
Schaller, Michael
The united states and China in the twentieth century
Oxford University press, 1979
 Buku Teks SO
Hu, Fengxiang
She hui bian ge yu wen hua chuan tong = Social change and cultural traditions = 社会变革与文化传统
shanghai renmin Chubansh, 2000
 Buku Teks