deletions | additions       diff --git a/preamble.tex b/preamble.tex  index 98415ea..365a870 100644  --- a/preamble.tex  +++ b/preamble.tex 
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\documentclass{article} \usepackage{amsfonts,amsmath,amssymb} \usepackage{graphicx} \usepackage{color} \usepackage{url} \bibliographystyle{plain} \setlength{\parindent}{1cm}