Merge branch 'Graph_database_2' of https://github.com/maieul/free-programming-books into maieul-Graph_database_2

free-programming-books.md

@@ -1484,7 +1484,8 @@ For resources on Angular, Backbone, D3, Dojo, Ember, Express, jQuery, Knockout,
 
 ### Neo4J
 
-* [Graph Databases](http://info.neotechnology.com/rs/neotechnology/images/GraphDatabases.pdf) (PDF)
+* [Graph Databases](http://info.neotechnology.com/rs/neotechnology/images/GraphDatabases.pdf) (v.1 - PDF)
+* [Graph Databases 2nd edition](http://neo4j.com/books/graph-databases/) (v.2 - just require to send some personnal data)
 
 
 ### .NET Framework