Hildebrand, David K., 1940-
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Buku Teks
edited by Jim Albert, Jay Bennett, James J. Cochran
Society for Industrial and Applied Mathematics, 2005
eBooks
Sheard, Rod
Spon Press, 2001
Buku Teks SO
Artikel Jurnal
Sternberg, Robert J.
American Psychological Association , 1999
Buku Teks