The webapp provides for each item the link on ECB's website.
Speeches for : Vitor Constancio where "theoretical" appeared
2018-05-04 : Past and future of the ECB monetary policy2017-09-25 : Developing models for policy analysis in central banks
2012-10-30 : Opening remarks at the second conference of the ESCB Macroprudential Research (MaRs) Network