--- a/CookBook/document/root.tex	Mon Oct 06 10:11:08 2008 -0400
+++ b/CookBook/document/root.tex	Thu Oct 09 12:58:50 2008 -0400
@@ -4,6 +4,7 @@
 \usepackage{isabellesym}
 \usepackage{charter}
 \usepackage[pdftex]{graphicx}
+\usepackage{proof}
 
 % Cross references to other manuals:
 \usepackage{xr}