Thanks to the initiative of Linked Open Data, the RDF datasets that are published on the Web are more and more numerous. One active research field currently concerns the problem of finding links between entities. We focus in this paper on ontology-based data linking approaches which use linking rules based on the available schemas (or ontologies). This kind of systems assume to have beforehand a set of mappings between ontology elements. However, this set of mappings could be incomplete. We propose in this paper a data linking approach called N2R-Part. It is based on the computation of similarity scores by exploiting at the same time properties for which a mapping exists and those for which there is no mapping. We illustrate throughout an example how the exploitation of the unmapped properties improves the data linking results.