I would like to thank all for very informative feedback. Apologies for the term "CIDAR" in my original email as I meant "CIDOC," which has been suggested by Dov Winer (and also by a CIDOC contact - see email below). Let's say CIDOC were used, what would be required to harmonize the CIDOC structure and nomenclature with WikiData conventions? Thanks also to Daniel Mietchen and his feedback and interest in learning more about what may be required to make this happen. I am including email below that provides information on CIDOC from Martin Doerr. Jeff Thompson raised the issue of CIDOC (an ISO standard) is behind a paywall, and I do not know what issues this raises. However, it touches on something the WD4R project will need to address - how to incorporate reference to, use of, and possible access to, valuable research information that is subscription-based (eg. Nature, Science). Has there been any consideration for two-tiered access to WD4R - a free basic access and a subscription access that may include access to Science, Nature and other valuable resources? Best regards - Sam --- The following note from Martin Doerr at ICS.forth.gr <CIDOC support> --- From: martin [mailto:martin@ics.forth.gr] Sent: Monday, December 29, 2014 5:46 AM To: Sam Smith Subject: Re: CIDOC or PAPYRUS as an Ontology for Historical Information Dear Mr. Smith, There are dozens or may be hundreds of CIDOC CRM extensions. Most do not come to our attention <This is in regard to the PAPYRUS history ontology project, that appears to be unused>. Many are created because people do not take their time to understand the concepts in depth. If they come in contact with us, we do everything to provide good consulting. Here, the creators extended the ontology with what we call "terminology", i.e., classes which do not introduce new relevant relationships in order to connect things to facts. They are just for classification, such as "forest". That does not make a "history ontology" in the proper sense. In confuses geographic classification and others with the core notion of history. We recommend to keep a system of concepts for classification, albeit a "formal ontology", separate from the ontology that provides relationship semantics. To our understanding, the CIDOC CRM has a fairly complete coverage of history in the mechanical sense. By coverage we mean to provide generalizations that cover the phenomena in the domain of interest. Specializations may elaborate general relationships into more specific patterns of behavior. For instance, Steffen Hennicke from the Humboldt University in Berlin is working on an extension of CRM to detail into things like political activities and archival recording, which introduces two or three new classes such as "expression of will". So, I'd recommend you just use CIDOC CRM as is, and combine via "P2 has type" with adequate vocabularies. If you like, I can subscribe you to crm-sig mailing list, then you can discuss directly with all experts. You are also kindly invited to join our next meeting in Oxford, Feb 9-12, and shortly present your project. Please do not hesitate to ask me any questions. As first reading, look at: http://www.cidoc-crm.org/cidoc_tutorial/index.html (better take the three hours time to see this!) and then recommendations on: http://www.cidoc-crm.org/comprehensive_intro.html Best season greetings, Martin