Porterfield, Gerald A.
McGraw-Hill, c1995
Buku Teks SO
Rubenstein, Harvey M.
New York: John Wiley & Sons, 1980
Buku Teks
American College of Radiology. Committee on Public Relations, Wendel G. Scott, chairman
Tear Book Publishers, 1953
Buku Referensi
Capezio, Peter J., 1947-
McGraw-Hill, 2010
Buku Teks
Beeby, C. E.
New Zealand Council for Educational Research, 1979
Buku Teks