--- doc/doxygen_manual.tex.orig	2015-02-28 15:26:54 UTC
+++ doc/doxygen_manual.tex
@@ -13,7 +13,7 @@
 % input used in their production; they are not affected by this license.
 
 \documentclass{book}
-\usepackage[a4paper,left=2.5cm,right=2.5cm,top=2.5cm,bottom=2.5cm]{geometry}
+\usepackage[left=2.5cm,right=2.5cm,top=2.5cm,bottom=2.5cm]{geometry}
 \usepackage{makeidx}
 \usepackage{natbib}
 \usepackage{graphicx}
