The last version of Repository Management with Nexus (aka The Nexus Book) was published along side the release of Nexus Repository Manager 3.5 and 2.14.5. Going forward, all documentation and help content for all Sonatype products is available at https://help.sonatype.com. If you are looking for previous versions of the Nexus Repository Manager documentation, it can be found here: https://books.sonatype.com/nexus-book/index.html. There will be no further updates to this repository as of August 1, 2017.