deletions | additions       diff --git a/bibliography/biblio.bib b/bibliography/biblio.bib  index 61d077e..9f03a1b 100644  --- a/bibliography/biblio.bib  +++ b/bibliography/biblio.bib 
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doi = {10.1186/1758-2946-3-s1-p4},  url = {http://dx.doi.org/10.1186/1758-2946-3-S1-P4},  year = {2011},  publisher = {Springer Science + $\mathplus$  Business Media}, volume = {3},  number = {Suppl 1},  pages = {P4},