# Representing and Validating Cultural Heritage Knowledge Graphs in CIDOC-CRM Ontology
## 2 Related Work  
Many recent studies have worked on mapping their cultural heritage datasets to CIDOC-CRM. Several archival studies used ISAD (G) (General International Standard Archival Description) and ISAAR (CPF) (International Standard Archival Authority Record for Corporate Bodies, Persons, and Families) in their mapping process to CIDOC-CRM.  
Figure 3: CIDOC-CRM is the semantic glue for cultural heritage datasets [5].  
The Portuguese National Archives were automatically migrated to the CIDOC-CRM standard [11]. The semantic migration process was applied according to both a predefined set of rules called \"Mapping Description Rules\" and both ISAD (G) and ISAAR recommendations. Other studies went with CIDOC-CRM after adding new classes and properties to its ontology to cover the source ontologies' entities, such as the level of description [12]. Another research [13] utilized CIDOC CRM and its extensions (CRMarchaeo, and CRM-sci) to represent archaeological excavation activities and the archaeologists' observations. The proposed data model could serve as the foundation for developing an automated system for archaeological documentation and data integration. Another research introduced two CIDOC-CRM extension proposals [14]. The innovative concepts of the multiple interpretation data model (MIDM) were mapped into the CIDOC CRM. The extension to CIDOC-CRM is required due to the fact that some MIDM concepts do not correspond to current CRM entities and properties. The mapping manuscript migrations (MMM) system aims to model and publish three heterogeneous manuscript databases (Bibale, Schoenberg Database, and Medieval Manuscripts in Oxford Libraries) [15]. The MMM data model is based on FRRBoo and CIDOC CRM [16]. SILKNOW is a research project that presents European silk heritage from the 15 th to the 19 th centuries in a semantic manner [17]. The used data model in SILKNOW is based on CIDOC-CRM. The Corago repository has historical data related to opera during the 16 th-20 th century [18]. This repository was translated into the Corago Semantic Model according to the CIDOC-CRM and FBRBoo ontologies. On the other hand, some studies preferred mapping to the Europeana Data Model (EDM) over CIDOC-CRM. EDM is easier to use for museums [19], although there is Linked Art, which follows CIDOC-CRM [20]. Linked Art is a linked open data-based model that provides patterns to publish data on art. The authors of the paper [19] investigated RDFization, which transforms raw data into RDF format, from the museums' viewpoint.  
The evaluation of the above mentioned mappings was limited to generating questions for researchers [11; 15], evaluating a sample set of archival records [12], submitting a questionnaire to several categories of users [18], or checking inferred properties and SPARQL queries [14].  
The introduced approach in this research shares common aspects and follows comparable steps to the papers [14; 18] in aligning with the CIDOC-CRM and adding additional classes and properties. However, the other approaches had quite different representations of historical facts and missed using SHACL constraint checking and rule inferencing for model validation. Consequently, this paper maps valuable data collection to CIDOC-CRM in order to be more formalized and accessible. It also demonstrates the applied mapping process in detail due to COURAGE characteristics which are different from the previously mentioned knowledge graphs. Due to this mapping, a validation process has to be implemented to check the COURAGE data and the mapping model. The paper shows the significant role of SHACL in validating both the mapping model and the data model. In conclusion, this paper has a novel approach by mapping the COURAGE dataset to CIDOC-CRM and validating the mapping and data models with both SHACL and SPARQL queries.