Browne, Michael E., author
McGraw-Hill, 2010
Buku Teks
Rosnow, Ralph L., author
McGraw-Hill, 1984
Buku Teks
This, Leslie E.
Addison-Wesley Pub. Co. , 1974
Buku Teks
Cliff, Norman, author
Lawrence Erlbaum Associates, 2003
Buku Teks
Rosenfeld, Louis, author
Mansell ; Neal-Schuman Publishers, 1995
Buku Referensi