Snedecor, George W.
Statistical methods
Iowa State University Press, 1989
 Buku Teks
Snedecor, George W.
Statistical methods
The Iowa State University Press, 1980
 Buku Teks
Snedecor, George W.
Statistical methods
The Iowa State University Press, 1982
 Buku Teks
Snedecor, George W.
Statistical methods
The Iowa State University Press, 1950
 Buku Teks
Chao, Lincoln L.
Statistics : methods and analysis
McGraw-Hill, 1974
 Buku Teks