(This article was first published on Software for Exploratory Data Analysis and Statistical Modelling » R Environment, and kindly contributed to R-bloggers)
This website provides a simple summary of the theme elements that can be set within ggplot2. There should be sufficient information here to change the default settings for graphs within the ggplot2 package.
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Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).