Eastman, Susan Tyler, author
Wadsworth, 1985
Buku Teks
Orlik, Peter B., author
Allyn & Bacon, 1994
Buku Teks
Anderson, Richard C., author
McGraw-Hill, 1960
Buku Teks
Husson, Samir S., author
Printice-Hall, 1970
Buku Teks
Rippin, Andrew, author
Routledge, 1990
Buku Teks