If the Digital Object Identifier, (DOI) is not listed, it might be found via a DOI locator.
If the DOI is longer than you prefer, try the DOI and URL shortner.
Basic rules and preferred link options for digital content:
If the source has a DOI, use the DOI.
If the source does not have a DOI, use the permalink.
If the source has neither a DOI or a permalink, use the URL.