I read somewhere in the documentation that it is considered best practice to register DOIs not just for articles, but for a nested structure like journal > issue > articles. However, I get seemingly mutually contradictory error message when trying to register issues. If I register issues and articles in the same batch, nesting the articles inside the issues like follows, then I get the error “Invalid content was found starting with element ‘journal_article’. No child element is expected at this point.“.
<journal_issue>
<journal_article>
</journal_article>
</journal_issue>
If I try registering them separately, without this nested structure, I get errors like: Invalid content was found starting with element ‘journal_issue’. One of ‘{“http://www.crossref.org/schema/5.3.1”:journal_article}’ is expected.
I have followed the examples given in documentation, as far as they go, but they don’t completely spell out this case.
Ideally, we would register articles and issues separately, in separate batches, as it would make for cleaner code on our side.
Our official best practice recommendation is to register DOIs for all journal articles and one DOI for the journal as a whole. But, it is not best practice to register DOIs for issues or volumes.
Crossref DOIs are intended as citation identifiers, so the general rule of thumb is that if something is likely to get cited, then it should be registered. Generally journal issues and volumes are not cited, so there’s really no benefit to registering DOIs for them, though you can if you really want to have those identifiers. (journals as a whole are also not typically cited, so there’s not really much practical benefit to registering journal-level DOIs either, but our schema has to support them for situations where there are no ISSNs)
In terms of why your xml isn’t validating, it sounds like some of the tagging is out of order, but we’d need to look at the file itself to know for sure. The community forum doesn’t allow file uploads, so we’ll have to take that question elsewhere. Could you send an email to support@crossref.org with that xml file attached?
Ah thanks. I can’t remember where I got the thing about registering issues too; perhaps something misremembered. Good that the recommendation is to not do this, as it seemed a bit odd to me anyway, and it will make it easier to handle the registration with just articles and the journal itself. There should be no problem with the XML if so.