Rörtgen, SteffenMandausch, MartinHenning, Peter A.2023-01-132023-01-132022https://dl.gi.de/handle/20.500.12116/39932The values for metadata attributes of Open Educational Resources (OER) are often made available in repositories without recourse to uniform value lists and corresponding standards. This circumstance complicates data harmonization when OERs from different sources are to be aggregated in one search environment. With the help of the RDF standard “SKOS” and the tool “SkoHub-Vocabs”, the project "WirLernenOnline" has found an innovative, reusable and standards-based solution to this challenge. This involves the creation of SKOS vocabularies that are used during the ETL process to harmonize differing terms (for example, "math" and "mathematics"). This then forms the basis for providing users with consistent filtering options and a good search experience. The created and open licensed vocabularies can then easily be reused and linked to overcome this challenge in the future.endata aggregationdata harmonizationETLOERRDFSKOSSkoHubText/Conference Paper10.18420/delfi2022-ws-71