permanence of mendeley's urls

Hi All,

We had a question on Friday's telecon about whether Mendeley's URLs are 
permanent. Here's what the Mendeley guys said:

mendeley_com @pgroth Generally: Yes! Though because we merge and 
collapse duplicates, in very few instances, the doc title (and hence 
URL) may change.

So I guess we can count on the urls. I guess the best suggestion then is 
to link to both the mendeley url and the doi url.

Thanks,
Paul