APA
(1968). Digest of educational statistics. Washington, USA: U.S. Government Printing Office.
Chicago
1968. Digest of educational statistics. Washington, USA: U.S. Government Printing Office.
Harvard
(1968). Digest of educational statistics. Washington, USA: U.S. Government Printing Office.
MLA
Digest of educational statistics. Washington, USA: U.S. Government Printing Office. 1968.
