Plummer, Charles C., author
WBC, 1991
Buku Teks
Skinner, Brian J., author
John Wiley & Sons, 1987
Buku Teks
Longwell, Chester R., author
John Wiley & Sons, 1969
Buku Teks
Plummer, Charles C., author
McGraw-Hill, 2013
Buku Teks
Tarbuck, Edward J., author
Maxwell Macmillan, 1993
Buku Teks