Smith, Read-Judith, author
South-Western, 2002
Buku Teks
Krevolin, Nathan
Prentice-Hall, 1986.
Buku Teks
Leahy, Emmett J.,
McGraw-Hill, 1965
Buku Teks
Maguire, Rachael, author
Facet Publishing, 2019
Buku Teks
Penn, Ira A., author
Gower, 1998
Buku Teks