Is there a permanent #ID for an article in Mendeley that will facilitate when assigning articles for

Is there a permanent #ID for an article in Mendeley that will facilitate when assigning articles for team of reviewers? I checked both Desktop and online Mendeley and was not able to find a consistent or permanent #ID (meaning it would not change if we keep adding more articles) for each article. Mendeley desktop, on the right side “details window” has the DOI, PMID field…however not every article have a DOI or PMID. I tried exporting to Refworks and importing back to Mendeley to see if a #ID was assigned…but had no luck. I would like to figure this out within the next 2 days if possible, so I can assign articles #ID to the team and we can get started with screening articles. Please let me know if you have any suggestions. Thank you!