deletions | additions       diff --git a/bibliography/biblio.bib b/bibliography/biblio.bib  index e2ca65f..bb835ac 100644  --- a/bibliography/biblio.bib  +++ b/bibliography/biblio.bib 
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}  @article{Thelwall_2013, @article{Thelwall_2013b,  doi = {10.1371/journal.pone.0064841},  url = {http://dx.doi.org/10.1371/journal.pone.0064841},  year = {2013},