http://gmfsamples.tuxfamily.org/wiki/doku.php?id=start
http://www.eclipse.org/articles/Article-Introducing-GMF/article.html
http://www.networkedlearning.nl/files/Getting%20started%20with%20GMF%20-%20working%20copy.pdf
http://wiki.eclipse.org/Graphical_Modeling_Framework/Tutorial/Part_1#Overview_of_GMF