XSLT = docbook.xsl
XSLTOPTS = --xinclude --stringparam html.stylesheet docbook-xsl.css
-user-manual.html: user-manual.xml
+user-manual.html: user-manual.xml $(XSLT)
$(QUIET_XSLTPROC)$(RM) $@+ $@ && \
xsltproc $(XSLTOPTS) -o $@+ $(XSLT) $< && \
mv $@+ $@