Eagles, Paul F.J.
Longman, 1984
Buku Teks
Usher, M.B.
Chapman and Hall , 1973
Buku Teks
Chiras, Daniel D., author
Pearson, 2014
Buku Teks
IlL. The University of Chicago Press , 1970
Buku Teks
Greenland, David, author
Charles E. Merrill, 1983
Buku Teks