Woelke, Manfred, author
Nasional Printers Pte, 1978
Buku Teks
Mead, R., author
Chapman & Hall, 1993
Buku Teks
Snedecor, George W., author
The Iowa State University Press, 1964
Buku Teks
Finney, D.J.
John Wiley & Sons, 1953
Buku Teks
Snedecor, George W., author
The Iowa State University Press, 1962
Buku Teks