I have found this document from the European Commission outlining EU rights of freedom of movement extremely clearly, but written for laypeople (as opposed to the 2004 EC law document) which is extremely helpful: https://www.sachsen.de/en/download/guide_free_movement_low.pdf
GNU social JP is a social network, courtesy of GNU social JP管理人. It runs on GNU social, version 2.0.2-dev, available under the GNU Affero General Public License.
All GNU social JP content and data are available under the Creative Commons Attribution 3.0 license.