1. Fully communication oriented NIAM;Bakema,1994
2. Subtyping: conceptual and logical issues;Halpin,1995
3. Halpin, T. 2007-2009, ‘Temporal modeling: parts 1–7’, Bus. Rules J., 8 and 9. Accessible at: www.BRCommunity.com and Modeling Issues page of www.orm.net.
4. Halpin, T. 2009-2013, ‘Ontological modeling: parts 1–15’, Bus. Rules J., 10–14. Accessible at www.BRCommunity.com and Modeling Issues page of www.orm.net.
5. Recent enhancements to ORM;Halpin,2013