diff --git a/apps/graph/graph/integral_graph_controller.cpp b/apps/graph/graph/integral_graph_controller.cpp
index 5ebb852a1..1e49258f2 100644
--- a/apps/graph/graph/integral_graph_controller.cpp
+++ b/apps/graph/graph/integral_graph_controller.cpp
@@ -36,7 +36,7 @@ double IntegralGraphController::cursorNextStep(double x, int direction) {
   return (direction > 0 ? x + m_graphRange->xGridUnit()/k_numberOfCursorStepsInGradUnit : x - m_graphRange->xGridUnit()/k_numberOfCursorStepsInGradUnit);
 }
 
-ExpressionLayout * IntegralGraphController::createFunctionLayout(const char * functionName) {
+LayoutReference IntegralGraphController::createFunctionLayout(const char * functionName) {
   char buffer[7] = "0(x)dx";
   buffer[0] = functionName[0];
   return LayoutHelper::String(buffer, strlen(buffer), KDText::FontSize::Small);
diff --git a/apps/graph/graph/integral_graph_controller.h b/apps/graph/graph/integral_graph_controller.h
index 5c0aaf8cc..685b8d1d1 100644
--- a/apps/graph/graph/integral_graph_controller.h
+++ b/apps/graph/graph/integral_graph_controller.h
@@ -14,7 +14,7 @@ public:
 private:
   I18n::Message legendMessageAtStep(Step step) override;
   double cursorNextStep(double position, int direction) override;
-  Poincare::ExpressionLayout * createFunctionLayout(const char * functionName) override;
+  Poincare::LayoutReference createFunctionLayout(const char * functionName) override;
 };
 
 }
diff --git a/apps/shared/sum_graph_controller.cpp b/apps/shared/sum_graph_controller.cpp
index 77025580f..14bc6290f 100644
--- a/apps/shared/sum_graph_controller.cpp
+++ b/apps/shared/sum_graph_controller.cpp
@@ -229,8 +229,8 @@ void SumGraphController::LegendView::setEditableZone(double d) {
  m_editableZone.setText(buffer);
 }
 
-void SumGraphController::LegendView::setSumSymbol(Step step, double start, double end, double result, ExpressionLayout * functionLayout) {
-  assert(step == Step::Result || functionLayout == nullptr);
+void SumGraphController::LegendView::setSumSymbol(Step step, double start, double end, double result, LayoutReference functionLayout) {
+  assert(step == Step::Result || functionLayout.isUninitialized());
   const char sigma[] = {' ', m_sumSymbol};
   if (step == Step::FirstParameter) {
     m_sumLayoutRef = LayoutHelper::String(sigma, sizeof(sigma));
diff --git a/apps/shared/sum_graph_controller.h b/apps/shared/sum_graph_controller.h
index e40a74bf8..010b2879c 100644
--- a/apps/shared/sum_graph_controller.h
+++ b/apps/shared/sum_graph_controller.h
@@ -39,7 +39,7 @@ private:
   constexpr static float k_cursorBottomMarginRatio = 0.28f; // (cursorHeight/2+bannerHeigh)/graphViewHeight
   virtual I18n::Message legendMessageAtStep(Step step) = 0;
   virtual double cursorNextStep(double position, int direction) = 0;
-  virtual Poincare::ExpressionLayout * createFunctionLayout(const char * functionName) = 0;
+  virtual Poincare::LayoutReference createFunctionLayout(const char * functionName) = 0;
   Shared::InteractiveCurveViewRange * interactiveCurveViewRange() override { return m_graphRange; }
   Shared::CurveView * curveView() override { return m_graphView; }
   TextFieldDelegateApp * textFieldDelegateApp() override {
@@ -58,7 +58,7 @@ private:
     void drawRect(KDContext * ctx, KDRect rect) const override;
     void setLegendMessage(I18n::Message message, Step step);
     void setEditableZone(double d);
-    void setSumSymbol(Step step, double start = NAN, double end = NAN, double result = NAN, Poincare::ExpressionLayout * sequenceName = nullptr);
+    void setSumSymbol(Step step, double start = NAN, double end = NAN, double result = NAN, Poincare::LayoutReference sequenceName = Poincare::LayoutReference());
   private:
     constexpr static KDCoordinate k_legendHeight = 35;
     constexpr static KDCoordinate k_editableZoneWidth = 12*KDText::charSize(KDText::FontSize::Small).width();