deletions | additions       diff --git a/bibliography/biblio.bib b/bibliography/biblio.bib  index 23c7cea..a4642b3 100644  --- a/bibliography/biblio.bib  +++ b/bibliography/biblio.bib 
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doi = {10.1186/1758-2946-1-12},  url = {http://dx.doi.org/10.1186/1758-2946-1-12},  year = {2009},  publisher = {Springer Science + $\mathplus$  Business Media}, volume = {1},  number = {1},  pages = {12},