Thomason, Michael, author
Reston Publishing, 1979
Buku Referensi
editors, Richard C. Johnson, Henry Jasik
McGraw-Hill, 1987
Buku Referensi
Beach, David P.
Delmar Pub, 1991
Buku Teks
Chang, William S.C.
Addison-Wesley Pub. Co., 1969
Buku Teks
Millman, Jacob, author
McGraw-Hill, 1978
Buku Teks