sentences:  The official reactions to Sinn's research findings were mixed.At first, in February and March 2011, the Bundesbank downplayed the TARGET balances as an irrelevant statistical position.However, in early 2012, Bundesbank chief Jens Weidmann wrote a letter to ECB head Mario Draghi on the subject which "found its way into the columns of the conservative "Frankfurter Allgemeine Zeitung" newspaper.