diff --git a/documentation/poky-ref-manual/Makefile b/documentation/poky-ref-manual/Makefile
index f686304f3d..eff947c6ee 100644
--- a/documentation/poky-ref-manual/Makefile
+++ b/documentation/poky-ref-manual/Makefile
@@ -20,7 +20,7 @@ XSLTOPTS = --stringparam html.stylesheet style.css \
            --stringparam  appendix.autolabel A \
            --stringparam  section.autolabel 1 \
            --stringparam  section.label.includes.component.label 1 \
-	   --xinclude
+         --xinclude
 
 VER = 1.0
 DOC = poky-ref-manual