References

1. Bertin, Jacques, Semiology of Graphics. The University of Wisconsin Press, Madison, 1983. Translated by William J. Berg.
2. Kaufman, Leonard, and Peter Rousseeuw, Finding Groups in Data - An Introduction to Cluster Analysis. John Wiley & Sons, Inc., Belgium, 1990.
3. Reynolds, H.T., Analysis of Nominal Data. Sage Publications, Beverly Hills, 1977.
4. Tufte, Edward R., Envisioning Information. Graphics Press, Cheshire, 1990.
5. Tufte, Edward R., The Visual Display of Quantitative Information. Graphics Press, Cheshire, 1983.
6. Wise, James A., et al., Visualizing the Non-Visual. Proceedings of Visualization '95, pages 51-58. IEEE Computer Society Press, Los Alamitos, California, 1995.