This presentation will explain and demonstrate the potential of a Reference Ontology (RO) in solving interoperability issues of bibliographic ontologies derived not only from misalignments in granularity and meaning of certain elements but also from their reduced application of semantic mechanisms (e.g., classification, equivalence, hierarchy or transitivity), and the low level of interlinking among ontologies. These problems require methods alternative to mapping techniques, such as crosswalks and application profiles, which are poorly scalable and not best suited for the Semantic Web. The proposed RO is intended for such mediation, i.e., for connecting different ontologies at a higher level and without imposing a common central ontology. It is built on RDFS/OWL (Resource Description Framework Schema/Web Ontology Language) abstraction and inference mechanisms and mediation techniques for interconnecting ontologies. It also makes use of SHACL (Shapes Constraint Language) to overcome RDFS/OWL inability to impose and validate data restrictions, an aspect important in the interoperation of bibliographic ontologies to avoid inconsistencies. RO demonstration will focus on solving two interoperability problems of RDA (Resource Description and Access) and BIBFRAME (Bibliographic Framework Initiative): i) the polysemy of the bf:Work class (multiple correspondence between bf:Work and RDA concepts of Work and Expression); and ii) the lack of transitivity, non-reflexivity and asymmetry in RDA and BIBFRAME formalization of whole-part relationships. The RO will be applied to real-world bibliographic examples from the Library of Congress and the Biblioteca Nacional de España datasets. Both the RO main components (OWL and SHACL RDF/XML files) and the bibliographic examples datasets are available at https://libraryreferenceontology.com.