Codes from terminologies, value sets, and terminologies themselves can all be identified by IHTSDO standard URIs. Use of these may proliferate in the future. We need to describe how DV_CODED_TEXT should be populated to use them. Possibly the best approach is to consider terminology_id a namespace string that maps to a standard URI for each terminology, which will be published by openEHR in a table. Code strings could be treated the same way.