Gaya APA
SNEDECOR, G, W., COCHRAN, W, G. (1956).
Statistical methods : (5th ed.).
Ames:
The Iowa State University Press.
Gaya MLA
SNEDECOR, George, W.., COCHRAN, William, G..
"Statistical methods :".
5th ed.
Ames:
The Iowa State University Press,
1956.
Buku.