Languages and geo-coded Wikipedia articles in Spain

Interesting article on "Geographic intersections of languages in Wikipedia": http://geography.oii.ox.ac.uk/2013/12/geographic-intersections-of-languages-in-wikipedia/

See the main map by clicking on "Més informació" below.

"The project was developed using geo-coded Wikipedia articles from the Wikimedia Toolsever Ghel project (Geohack External Links), and article metrics that were collated using Toolserver scripts. The Ghel data dumps date to July 2013."

See another study with maps of Catalan and other languages, based on tweets: 
http://estudiscatalans.blogspot.com/2013/10/tweets-in-catalan.html