diff --git a/src/build_models/auxingrowthplugin.h b/src/build_models/auxingrowthplugin.h
--- a/src/build_models/auxingrowthplugin.h
+++ b/src/build_models/auxingrowthplugin.h
@@ -37,7 +37,7 @@ public:
 	virtual QString ModelID(void) { return QString( "Auxin accumulation and growth" ); }
 	
 	// Executed after the cellular mechanics steps have equillibrized
-	virtual void CellHouseKeeping (CellBase &c);
+	virtual void CellHouseKeeping (CellBase *c);
 	// Differential equations describing transport of chemicals from cell to cell
 	virtual void CelltoCellTransport(Wall *w, double *dchem_c1, double *dchem_c2);
     
@@ -49,15 +49,15 @@ public:
 	virtual void CellDynamics(CellBase *c, double *dchem);
 	
 	// to be executed after a cell division
-	virtual void OnDivide(ParentInfo &parent_info, CellBase &daughter1, CellBase &daughter2);
+	virtual void OnDivide(ParentInfo *parent_info, CellBase *daughter1, CellBase *daughter2);
 	
 	// to be executed for coloring a cell
-	virtual void SetCellColor(CellBase &c, QColor &color);	
+	virtual void SetCellColor(CellBase *c, QColor *color);	
 	// return number of chemicals
 	virtual int NChem(void) { return 2; }
 	
 private:
-	double complex_PijAj(CellBase &here, CellBase &nb, Wall &w);
+	double complex_PijAj(CellBase *here, CellBase *nb, Wall *w);
 };
 
 #endif