Ellis, Donald
Lawrence Erlbaum Asssociates, Publish., 1999
Buku Teks
Schon, Donald A.
Penguin Books, 1973
Buku Teks
Adams, Robert McC.
ALdine Publishing Company, 1966
Buku Teks
Sims, Newell Leroy
D. Appleton , 1924
Buku Teks
Luard, Evan, author
St. Martin`s Press, 1992
Buku Teks