deletions | additions       diff --git a/header.tex b/header.tex  index 083ea1f..492282c 100644  --- a/header.tex  +++ b/header.tex 
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%\usepackage{natbib}  \newcommand{\catme}{\href{http://www.catme.org}{CATME}}  \newcommand{\ipython}{iPython} \newcommand{\ipython}{\href{http://ipython.org/notebook.html}{iPython}}