1. http://schema.org/docs/schemas.html
2. http://json-ld.org/spec/latest/

3. https://support.google.com/webmasters/answer/4620709

4. http://learningregistry.org/

5. http://blog.heppresearch.com/2014/03/24/json-ld-finally-google-honors-invisible-data-for-seo/

7. http://link.springer.com/chapter/10.1007%2F978-3-642-41338-4_2 (pdf at http://dws.informatik.uni-mannheim.de/fileadmin/lehrstuehle/ki/pub/Bizer-etal-DeploymentRDFaMicrodataMicroformats-ISWC-InUse-2013.pdf )

8. http://semanticweb.com/schema-org-chat-googles-r-v-guha_b40607

9. https://support.google.com/customsearch/answer/4544182?hl=en 
