deletions | additions       diff --git a/header.tex b/header.tex  index a433817..b0bdf98 100644  --- a/header.tex  +++ b/header.tex 
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\usepackage[square,numbers]{natbib}  \bibliographystyle{acm} \bibliographystyle{plainnat}  \usepackage{geometry}  \geometry{  letterpaper,  left=20mm,  right=20mm,  top=20mm,  bottom=30mm,  }