Maybe add https://google.github.io/styleguide/Rguide.xml and use the style as well on the pages in this wiki?
Feel free to add any link you find useful. Syntax highlighting for R in this wiki is done with the help of GeSHi, e.g.:
<source lang='rsplus'> a<-2 a </source>
--Oliver.gubler 14:34, 9 December 2015 (CET)