Please add books about wiki to this list:

* TheWikiWay
* LesWikis (French book, by Jerome Delacroix)
* WikiBookErikMoeller (German book, sister site link will turn up soon)
* WikiWebCollaboration, by AnjaEbersbach et al. (English translation of a German book, sister site links will turn up soon) 
* WikiBookChristophLange (German book, sister site link will turn up soon)
* WikiPatternsBook (English book about creating and managing a successfull wiki, based on the website Wikipatterns.com)