diff --git a/src/insets/InsetTOC.cpp b/src/insets/InsetTOC.cpp
index fc1f42bcae..11662ce9eb 100644
--- a/src/insets/InsetTOC.cpp
+++ b/src/insets/InsetTOC.cpp
@@ -148,7 +148,7 @@ void InsetTOC::makeTOCEntry(XHTMLStream & xs,
 }
 
 
-void InsetTOC::makeTOCWithDepth(XHTMLStream xs, 
+void InsetTOC::makeTOCWithDepth(XHTMLStream & xs, 
 		Toc toc, OutputParams const & op) const
 {
 	Toc::const_iterator it = toc.begin();
@@ -206,7 +206,7 @@ void InsetTOC::makeTOCWithDepth(XHTMLStream xs,
 }
 
 
-void InsetTOC::makeTOCNoDepth(XHTMLStream xs, 
+void InsetTOC::makeTOCNoDepth(XHTMLStream & xs, 
 		Toc toc, const OutputParams & op) const
 {
 	Toc::const_iterator it = toc.begin();
diff --git a/src/insets/InsetTOC.h b/src/insets/InsetTOC.h
index ead482b2e8..183683628d 100644
--- a/src/insets/InsetTOC.h
+++ b/src/insets/InsetTOC.h
@@ -64,9 +64,9 @@ public:
 
 private:
 	///
-	void makeTOCWithDepth(XHTMLStream xs, Toc toc, const OutputParams & op) const;
+	void makeTOCWithDepth(XHTMLStream & xs, Toc toc, const OutputParams & op) const;
 	///
-	void makeTOCNoDepth(XHTMLStream xs, Toc toc, const OutputParams & op) const;
+	void makeTOCNoDepth(XHTMLStream & xs, Toc toc, const OutputParams & op) const;
 	///
 	void makeTOCEntry(XHTMLStream & xs, Paragraph const & par, OutputParams const & op) const;