Roth, Leland M
Harper & Row Publishers, 1979
Buku Teks
editor Thomas C. Cochran, Wayne Andrew
Charles Scribner's Sons , 1962
Buku Referensi
Brinkley, Alan, author
McGraw-Hill, 1997
Buku Referensi
Bukowski, Douglas, author
Bedford/St. Martin's, 1999
Buku Teks
Bukowski, Douglas, author
Bedford/St. Martin's, 1999
Buku Teks