The webapp provides for each item the link on ECB's website.
Speeches for : Tommaso Padoa-Schioppa where "enlargement" appeared
2004-10-21 : Enlargement and “old” Europe: Blow or Blessing?2002-03-22 : Accession Countries on the Way to the Euro: A Central Banker's View,
1999-11-12 : ECB press conference following the Helsinki seminar on the EU accession process