Active Object-Oriented Database Design Using Active Object/Behavior Diagrams. - Peter Bichler; Michael Schrefl (RIDE-ADS, 1994)

Inheritance of Business Rules. - Peter Bichler; Michael Schrefl (Grundlagen von Datenbanken, 1995)

Workflow Transparency. - Peter Bichler; Günter Preuner; Michael Schrefl (CAiSE, 1997)