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Harcourt, Brace, 1951
Buku Teks
edited by Freddie H. Fu, Steven B. Cohen
Slack Incorporated, 2008
Buku Teks
World Bank
World Bank Office Jakarta, 2011.
Buku Teks
Natterer, Frank, author
Society for Industrial and Applied Mathematics, 2001
eBooks
Russell, Bertrand, 1872-1970, author
Routledge , 1997
Buku Teks