Greenewalt, Crawford H., 1902-1993
McGraw-Hill, 1959
Buku Teks SO
Fleisher, Lee A
Elsevier Saunder, 2012
Buku Teks SO
Dye, Thomas R.
Harcourt Brace College, 2000
Buku Teks SO
Dye, Thomas R.
Thomson, 2006
Buku Teks SO
Collins, Jim
Routledge, 1989
Buku Teks SO