diff --git a/Documentation/Makefile b/Documentation/Makefile
index eecc27aba2..3e317b8c1c 100644
--- a/Documentation/Makefile
+++ b/Documentation/Makefile
@@ -120,6 +120,7 @@ INSTALL_INFO = install-info
 DOCBOOK2X_TEXI = docbook2x-texi
 DBLATEX = dblatex
 ASCIIDOC_DBLATEX_DIR = /etc/asciidoc/dblatex
+DBLATEX_COMMON = -p $(ASCIIDOC_DBLATEX_DIR)/asciidoc-dblatex.xsl -s $(ASCIIDOC_DBLATEX_DIR)/asciidoc-dblatex.sty
 ifndef PERL_PATH
 	PERL_PATH = /usr/bin/perl
 endif
@@ -368,7 +369,7 @@ user-manual.texi: user-manual.xml
 
 user-manual.pdf: user-manual.xml
 	$(QUIET_DBLATEX)$(RM) $@+ $@ && \
-	$(DBLATEX) -o $@+ -p $(ASCIIDOC_DBLATEX_DIR)/asciidoc-dblatex.xsl -s $(ASCIIDOC_DBLATEX_DIR)/asciidoc-dblatex.sty $< && \
+	$(DBLATEX) -o $@+ $(DBLATEX_COMMON) $< && \
 	mv $@+ $@
 
 gitman.texi: $(MAN_XML) cat-texi.perl texi.xsl