Calvert, James, author
McGraw-Hill, 1994
Buku Teks
Weber, Jean E., author
Harper & Row, 1982
Buku Teks
Lial, Margareth L., author
Scott, Foresman, 1979
Buku Teks
Silver, Howard A.
Prentice-Hall, 1979
Buku Teks
Lial, Margaret L., author
Harper Colins, 1995
Buku Teks