vcd & vcdExtra http://cran.r-project.org/web/packages/vcd/ http://cran.r-project.org/web/packages/vcdExtra/
Tutorial cran.r-project.org/web/packages/vcdExtra/vignettes/vcd-tutorial.pdf
datavis.ca - categorical data http://www.datavis.ca/courses/grcat/
datavis.ca - visualizing categorical data http://www.datavis.ca/courses/VCD/
Penn State STAT 504 - Analysis of Discrete Data https://onlinecourses.science.psu.edu/stat504/node/207
Pilh�ofer & Unwin, "New Approaches in Visualization of Categorical Data: R Package extracat", Journal of Statistical Software, 2013 (53:7) http://www.jstatsoft.org/v53/i07/paper
Bilder & Loughin, *Analysis of Categorical Data with R", Chapman & Hall, 2014 http://www.crcpress.com/product/isbn/9781439855676
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