ConceptBase by Roberto Zicari · Published January 1, 2008 · Updated February 16, 2014 Tilburg University ConceptBase is a multi-user deductive and object-oriented database system for meta modeling and method engineering (FreeBSD-style license) LINK
Perst. Open Source, Object-Oriented Embedded Database January 1, 2009 by Roberto Zicari · Published January 1, 2009 · Last modified March 12, 2019
McObject January 1, 2009 by Roberto Zicari · Published January 1, 2009 · Last modified February 16, 2014
Asking SBQL queries addressing imported XML files January 1, 2006 by Roberto Zicari · Published January 1, 2006 · Last modified February 18, 2014