Schwartz, Louis B., author
The Foundation , 1966
Buku Teks
Baldwin, William Lee, author
Richard D. Irwin, 1987
Buku Teks
Coll, Steve, 1958-, author
Penguin Books, 2012
Buku Teks
Fusilier, H. Lee
Prentice-Hall, 1971
Buku Teks
Richard D. Irwin, Inc., 1958
Buku Teks