Mead, R., author
Chapman & Hall, 1993
Buku Teks
Snedecor, George W., author
The Iowa State University Press, 1964
Buku Teks
Snedecor, George W., author
The Iowa State University Press, 1962
Buku Teks
Bailley, Norman T. J., author
Cambridge University Press, 1992
Buku Teks
Woelke, Manfred, author
Nasional Printers Pte, 1978
Buku Teks