I was reading Extracting tree crown areas from remote sensing data (visual images and LiDAR) with interest and saw a comment made by @Aaron about links to documents breaking and how answers should be better than a 1 liner.
This got me thinking after I had followed the link to the paper. Just about any decent Journal utilises the DOI. So my suggestion and I have no idea how difficult it would be to implement in GIS StackExchange is to have another button or augment the current link button to allow a user to specifically enter the DOI number. In theory @Aarons arguments should go away as the DOI is unique and persists.
Just an idea?