The IMFS Working Paper "Estimating the European Central Bank's 'Extended Period of Time'" by Tilman Bletzinger and Volker Wieland is extensively presented in the German Börsen-Zeitung on 5.9.2013. Summary versions are also published on VoxEU.org and CBNC.
These are the links to the articles:
The IMFS Working Paper can be found here.
Update:
Recently on November 3, 2013, Gavyn Davies uses the results of this IMFS Working Paper in his Financial Times Blog.