The Arabidopsis Book chapters are citable. The official publication date is the date the paper is first published online and can be found at http://www.bioone.org/action/showBook?doi=10.1199%2Ftab.book. Chapters are assigned Digital Object Identifiers (DOIs), unique identifiers for intellectual property in the digital environment (e.g., doi: 10.1199/tab.0009). A sample citation of a chapter in The Arabidopsis Book: