deletions | additions       diff --git a/bibliography/biblio.bib b/bibliography/biblio.bib  index 950b2de..7a27708 100644  --- a/bibliography/biblio.bib  +++ b/bibliography/biblio.bib 
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title = {The theory of matrices},  year = {1960}  }  @book{Apostol1967,  Address = {New York, NY},  Author = {Tom M Apostol},  Editor = {George Springer},  Publisher = {John Wiley & Sons},  Title = {Calculus},  Volume = {1},  Year = {1967}  }  @book{Apostol1969,  Address = {New York, NY},  Author = {Tom M Apostol},  Editor = {George Springer},  Publisher = {John Wiley & Sons},  Title = {Calculus},  Volume = {2},  Year = {1969}  }