Scott, Peter, author
Huytchinson University Library , 1970
Buku Teks
Pounds, Norman J. G., author
McGraw-Hill, 1972
Buku Teks
[publisher not identified], [date of publication no identified]
Buku Teks
Kendall, Henry M., author
Harcourt, Brace & World, 1962
Buku Teks
Pounds, Norman J. G., author
Silver Burdett, 1980
Buku Teks