Interoperability is a key problem in agent-based systems where different interacting computational entities negotiate to achieve a common goal. In last years, this interoperability issue has been faced by exploiting the concept of ontology that enables a single agent to model its knowledge by means of a semantic description of a domain of interest. However, ontology ability to enable a full interoperability can be limited by the so-called semantic heterogeneity problem which arises when some discrepancies exist among ontologies modeling the knowledge related to different agents. As consequence, in order to enable an effective knowledge exchange, an ontology alignment process is necessary to lead proprietary ontologies to a mutual agreement....