deletions | additions       diff --git a/bibliography/biblio.bib b/bibliography/biblio.bib  index 9486773..8d941d6 100644  --- a/bibliography/biblio.bib  +++ b/bibliography/biblio.bib 
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year = {2013},  publisher = {IEEE},  }  @book{olufemi2012assessing,  title = {{Assessing the Levels of Awareness, Knowledge and Attitude about Environmental Pollution as Well as the Presence of Pollutants in the Vicinity of Schools in a Coal Mining Area}},  author = {Olufemi, A.C.},  url = {https://books.google.com.ph/books?id=xLzDoAEACAAJ},  year = {2012},  }