diff --git a/ws/Docbook/Preprocess/make.rules b/ws/Docbook/Preprocess/make.rules
index 484b7d9c101824ab2f55c8244bc308d3ea5df9a0..0855ce49d34bc5a9b5a3af4f46451f8cd8c4164e 100644
--- a/ws/Docbook/Preprocess/make.rules
+++ b/ws/Docbook/Preprocess/make.rules
@@ -87,7 +87,7 @@ SAXONCMD=java -cp "${DBOOK_XSL}/tools/lib/saxon9he.jar:/usr/share/java/xercesImp
 	 ${SAXONCMD} -s:$*.xml \
             -xsl:${DBOOK_XSL_PREPROCESS}/Xsl/docbook2print.xsl > ${*}.print.xml
 	cd  $(@D); ${SAXONCMD} -s:$(<F) -xsl:${DBOOK_XSL_PREPROCESS}/Xsl/docbookExtractFig.xsl
-	tar cv- `find . -name Ref -and -type d|grep -v ^\./target`|tar -x -C $(@D)
+	tar cv- `find . -name Ref -and -type d|grep -v ^\./target`|tar -x -C $(@D) || echo
 	cp -f ${DBOOK_XSL_PREPROCESS}/make.image ${DBOOK_XSL_PREPROCESS}/docbooksupplement.js $(@D)
 	cd  $(@D); $(MAKE) -j ${numCores} -f make.image; rm -rf `find . -name Generate`