As someone with a hardly any interest in this problem it seems to me that this isn't a great paper.
To discuss this without mentioning the multiple downloadable citation networks or any mention of basic graph analysis techniques (centrality measures or graph cut counts seem relevant here) seems a pretty big oversight.
Yeah, that phrase serves zero actual purpose. That, combined with the sloppy language in the rest of the paper makes me doubt the scientific detachment of these people.
You also find the same problem on link sharing services (like this one) in that they're extremely easy to game. I have yet to see a paper that proposes a good solution for that kind of thing.
This is a problem that Google has largely solved. Its original PageRank algorithm was prone to citation networks inflating the value of a page. Nowadays, link farms have lost much of their power.
To discuss this without mentioning the multiple downloadable citation networks or any mention of basic graph analysis techniques (centrality measures or graph cut counts seem relevant here) seems a pretty big oversight.
The did mention doping in cycling through.