Mendenhall, William
Duxbury Press, 1981
Buku Teks SO
Devore, Jay L.
Springer, 2012
eBooks
Hoel, Paul Gerhard, 1905-
John Wiley & Sons, 1962
Buku Teks SO
Kapadia, Asha Seth
Chapman & Hall/CRC, 2005
Buku Teks SO
Larsen, Richard J.
Prentice-Hall, 1981
Buku Teks SO