Merge pull request #2116 from obophenotype/editing_guidelines.md_URL_…

…dbxref

Update guidance on adding URL dbxrefs (editing_guidelines.md)

docs/editing_guidelines.md

@@ -113,21 +113,20 @@ ORCID identifiers may also be used when the only available source for an asserti
 
 **Technical details of adding a cross-reference using Protégé**:
 
-For CURIEs and ORCIDs: In the "Create Annotation" window, select the annotation property **database_cross_reference**.
+For CURIEs, ORCIDs: In the "Create Annotation" window, select the annotation property [**database_cross_reference**](http://www.geneontology.org/formats/oboInOwl#hasDbXref).
+For adding URLs to text definitions or synonyms:  In the "Create Annotation" window, select the annotation property [**database_cross_reference**](http://www.geneontology.org/formats/oboInOwl#hasDbXref).
+For adding URLs to axioms that are NOT text definitions or synonyms:  In the "Create Annotation" window, select the annotation property [**source**](http://www.geneontology.org/formats/oboInOwl#source).
 
 For CURIEs: Enter the CURIE, using the [bioregistry OBO context](https://bioregistry.io/context/obo) prefix ([link to prefixmap](https://github.com/biopragmatics/bioregistry/blob/main/exports/contexts/obo.context.jsonld)), as a Value on the "Literal" tab. Leave Datatype empty.
 
 In cases where more than one CURIE is available for a resource, either is acceptable, but using the more semantically specific identifier is recommended. For example, when both a PMID and a doi are available for a resource, using the PMID is recommended since it indicates the cross-reference points to a paper, as opposed to a doi which could point to any digital object.
 
 For ORCIDs: Enter the ORCID as an IRI in the IRI field on the "IRI Editor" tab, for example `https://orcid.org/0000-0002-7356-1779`.
 
-For URLs: In the "Create Annotation" window, select the annotation property **'see also'** (`rdfs:seeAlso`). Enter the URL as a literal string with Datatype `xsd:anyURI` selected.
-DO NOT use database_cross_reference with a value that is a URL. 
+For URLs: Enter the URL as a literal string with Datatype `xsd:anyURI` selected.
 
 To restate, in all cases above except ORCIDs, the values are entered as literal strings. An ORCID MUST BE entered as an IRI.
 
-The above instructions apply whether the cross-reference is added to another annotation (e.g., annotating a text defintion or comment) or adding to the overall class (i.e., not an annotation of another annotation). 
-
 ## Term contributors
 
 When adding an ORCID to identify a term contributor, in the "Create Annotation" window, select the annotation property **dcterms:contributor**. The ORCID is still entered as an IRI on the “IRI Editor” tab.