deletions | additions       diff --git a/bibliography/biblio.bib b/bibliography/biblio.bib  index 3970be4..bc4365e 100644  --- a/bibliography/biblio.bib  +++ b/bibliography/biblio.bib 
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@book{Burke_1997,  url = {http://staff.ustc.edu.cn/~wzhao7/c_index_files/main.files/HJMo.pdf},  year = {1997},  publisher = {Cambridge University Press ({CUP})},  author = {Bernard F Burke and Francis Graham-Smith},  title = {{An introduction to radio astronomy}},  }  @book{Mo_2009,  doi = {10.1017/cbo9780511807244},  url = {http://dx.doi.org/10.1017/cbo9780511807244},  year = {2009},  publisher = {Cambridge University Press ({CUP})},  author = {Houjun Mo and Frank van den Bosch and Simon White},  title = {{Galaxy Formation and Evolution}},  }  @incollection{Djorgovski_2013,  doi = {10.1007/978-94-007-5618-2_5},  url = {http://dx.doi.org/10.1007/978-94-007-5618-2_5}, 
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}  @book{Burke_1997,  url = {http://staff.ustc.edu.cn/~wzhao7/c_index_files/main.files/HJMo.pdf},  year = {1997},  publisher = {Cambridge University Press ({CUP})},  author = {Bernard F Burke and Francis Graham-Smith},  title = {{An introduction to radio astronomy}},  }  @book{Mo_2009,  doi = {10.1017/cbo9780511807244},  url = {http://dx.doi.org/10.1017/cbo9780511807244},  year = {2009},  publisher = {Cambridge University Press ({CUP})},  author = {Houjun Mo and Frank van den Bosch and Simon White},  title = {{Galaxy Formation and Evolution}},  }