Changes

The references for these papers were then matched against one another to produce counts of the most cited papers within the core group. This process led to 313 papers that were cited by more than one paper in the core group. Of these 239 were not in the original sample of 251. Each of these 239 papers was briefly checked to see whether it should be added to the core group and 8 papers were added.

Beginning with candidates for the up, we need to add custom BibTeX tags to each reference.