Clark, Brian D., author
Mansell, 1980
Buku Teks
Eccleston, Charles H., author
CRC Press, Taylor & Francis Group, 2011
Buku Teks
Westman, Walter E.
John Wiley & Sons, 1985
Buku Teks
Gilpin, Alan, author
Cambridge University Press, 1996
Buku Teks
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