Dimensional Analysis to Clarify Relations among the Top-Level Concepts of an Upper Ontology: Process, Event, Substance, Object. - Patrick Cassidy (CICLing, 2003)

The 2006 Upper Ontology Summit Joint Communiqué. - Leo Obrst; Patrick Cassidy; Steve Ray; Barry Smith 001; Dagobert Soergel; Matthew West 002; Peter Yim (Appl. Ontology, 2006)

Toward an Open-Source Foundation Ontology Representing the Longman's Defining Vocabulary: The COSMO Ontology OWL Version. - Patrick Cassidy (OIC, 2008)