How do I handle inaccessible DOIs when citing papers?
I'm from Crossref. The DOI should always resolve to some location, even if the content has moved location on the web or has changed publisher. Can you share the example so we can get it reported? It's possible it's not a Crossref DOI of course (there are several other DOI agencies) but I can find out from the DOI. The prefix does often denote a particular publisher but journals change hands frequently as societies negotiate different publishing agreements so that's not necessarily a failsafe way to solve the problem (which I agree should not be your problem!). Happy to help if you share the example(s) :-)