The webapp provides for each item the link on ECB's website.
Speeches for : Peter Praet where "heterogeneity" appeared
2017-05-24 : Europe’s economic recovery: challenges and opportunities for the banking sector2013-10-18 : Household heterogeneity and the transmission mechanism
2012-06-15 : Heterogeneity in a monetary union: What have we learned?
2011-12-09 : The State of the global economy