Rosnow, Ralph L., author
McGraw-Hill, 1984
Buku Teks
editor, James R. Newman
Harper & Row, 1963
Buku Referensi
Casti, John L.
William Morrow , 2000
Buku Teks
Bodner, George M.
John Wiley & Sons, 1995
Buku Teks
The American Society for Information Science , 1998
Buku Referensi