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Stuart~K. Card, Jock~D. Mackinlay, and Ben Shneiderman.
\newblock {\em Readings in Information Visualization: Using Vision to Think}.
\newblock Morgan Kaufmann, 1999.
\newblock URL: \url{https://dl.acm.org/citation.cfm?id=300679}.

\bibitem{ColorBrewer}
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\newblock Accessed February 4, 2019.
\newblock URL: \url{http://colorbrewer2.org/}.

\bibitem{Fekete2008}
Jean-Daniel Fekete, Jarke~J. van Wijk, John~T. Stasko, and Chris North.
\newblock The value of information visualization.
\newblock In Andreas Kerren, John~T. Stasko, Jean-Daniel Fekete, and Chris
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\newblock \href {http://dx.doi.org/10.1007/978-3-540-70956-5_1}
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\bibitem{Shneiderman1996}
Ben Shneiderman.
\newblock The eyes have it: A task by data type taxonomy for information
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\newblock In {\em Proceedings of the IEEE Symposium on Visual Languages},
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\bibitem{VanWijk2006a}
Jarke~J. {Van Wijk}.
\newblock Bridging the gaps.
\newblock {\em IEEE Computer Graphics and Applications}, 26(6):6--9, November
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\end{thebibliography}