diff --git a/src/insets/InsetTOC.cpp b/src/insets/InsetTOC.cpp
index 11662ce9eb..d413892a05 100644
--- a/src/insets/InsetTOC.cpp
+++ b/src/insets/InsetTOC.cpp
@@ -149,7 +149,7 @@ void InsetTOC::makeTOCEntry(XHTMLStream & xs,
 
 
 void InsetTOC::makeTOCWithDepth(XHTMLStream & xs, 
-		Toc toc, OutputParams const & op) const
+		Toc const & toc, OutputParams const & op) const
 {
 	Toc::const_iterator it = toc.begin();
 	Toc::const_iterator const en = toc.end();
@@ -207,7 +207,7 @@ void InsetTOC::makeTOCWithDepth(XHTMLStream & xs,
 
 
 void InsetTOC::makeTOCNoDepth(XHTMLStream & xs, 
-		Toc toc, const OutputParams & op) const
+		Toc const & toc, const OutputParams & op) const
 {
 	Toc::const_iterator it = toc.begin();
 	Toc::const_iterator const en = toc.end();
diff --git a/src/insets/InsetTOC.h b/src/insets/InsetTOC.h
index 183683628d..074ad535db 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 const & toc, const OutputParams & op) const;
 	///
-	void makeTOCNoDepth(XHTMLStream & xs, Toc toc, const OutputParams & op) const;
+	void makeTOCNoDepth(XHTMLStream & xs, Toc const & toc, const OutputParams & op) const;
 	///
 	void makeTOCEntry(XHTMLStream & xs, Paragraph const & par, OutputParams const & op) const;