deletions | additions       diff --git a/bibliography/biblio.bib b/bibliography/biblio.bib  index 51ab702..946ef6a 100644  --- a/bibliography/biblio.bib  +++ b/bibliography/biblio.bib 
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url = {http://dx.doi.org/10.1007/978-3-540-87849-0},  year = {2009},  publisher = {Springer Science $\mathplus$ Business Media},  title = {{Kalman Filtering}}, {Charles K. Chui, Guanrong Chen. Kalman Filtering. },  }