--- a/main.xsl
+++ b/main.xsl
@@ -28,6 +28,8 @@
                 </xsl:otherwise>
             </xsl:choose>
         </xsl:variable>
+
+        <xsl:processing-instruction name="xml-stylesheet">href="<xsl:value-of select="$files-prefix" />copy.xsl" type="text/xsl"</xsl:processing-instruction>
 
         <xsl:processing-instruction name="xml-stylesheet">href="<xsl:value-of select="$files-prefix" />main.css" type="text/css"</xsl:processing-instruction>