--- a/text/kw_macros.tex	Tue Aug 24 18:05:28 2010 -0700
+++ b/text/kw_macros.tex	Tue Aug 24 21:18:50 2010 -0700
@@ -29,6 +29,7 @@
 \def\vphi{\varphi}
 \def\inv{^{-1}}
 \def\ol{\overline}
+\def\BD{BD}
 
 \def\spl{_\pitchfork}