diff --git a/doc/Makefile b/doc/Makefile
index 518d3c9c3..eb9d82541 100644
--- a/doc/Makefile
+++ b/doc/Makefile
@@ -38,7 +38,7 @@ ifdef GH_TOKEN
 	git --work-tree=$(GH_PAGES) --git-dir=$(GH_PAGES)/.git config user.email "ol.sc@web.de"
 	$(RM) -r $(GH_PAGES)/doc
 	mkdir $(GH_PAGES)/doc
-	cp -R ../html/* $(GH_PAGES)/doc
+	cp ../html/* $(GH_PAGES)/doc
 	git --work-tree=$(GH_PAGES) --git-dir=$(GH_PAGES)/.git add -A doc
 	-git --work-tree=$(GH_PAGES) --git-dir=$(GH_PAGES)/.git commit -m "Updated doc from commit $(TRAVIS_COMMIT)."
 	git --work-tree=$(GH_PAGES) --git-dir=$(GH_PAGES)/.git push