I have a basic question about the documentation of the igraph R package. I see there is a .pdf on the CRAN mirror. There is also a considerably more lengthy "reference manual" on the sourceforge.net website. The date of the document on the CRAN mirror is May 8, 2009. And it appears that the "publication" date for the reference manual is 2006. Is this correct? If so, is the reference manual up to date with the latest version of igraph? More importantly, which do you recommend as an up to date manual on the software?