diff --git a/xml2xslt.xsl b/xml2xslt.xsl
index 5637823..5163e52 100644
--- a/xml2xslt.xsl
+++ b/xml2xslt.xsl
@@ -419,7 +419,7 @@
 \newcounter{exercise}
 \setcounter{exercise}{0}
 \newenvironment{exercise}%
-	{\noindent\refstepcounter{exercise}\begin{boxedminipage}{\columnwidth}\textbf{Exercise \theexercise:}}%
+	{\noindent\refstepcounter{exercise}\begin{boxedminipage}{\columnwidth}\textbf{Exercise \theexercise: }}%
 	{\end{boxedminipage}}
 
 </xsl-out:text>