Green, Bryan S.R.
Pergamon Press , 1966
Buku Teks
Bassis, Michael S., author
McGraw-Hill, 1991
Buku Teks
Gelles, Richard J., author
McGraw-Hill College , 1999
Buku Teks
Giddens, Anthony, author
W.W. Norton & Compan, 2005
Buku Teks
Gillin, John Lewis, author
Macmillan, 1942
Buku Teks