Moran, John Jude
Prentice-Hall, 2002
Buku Teks SO
Strecker, David E.
CRC Press Taylor & Francis Group, 2011
Buku Teks SO
Leslie, Douglas L.
West Publishing, 1992
Buku Teks SO
Gould, William B., IV
MIT Press, 1982
Buku Teks SO
Metz, Harold W.
The Brookings Institution, 1945
Buku Teks