diff --git a/EGkFrame3d.h b/EGkFrame3d.h
index 8f9d87c..5a013c6 100644
--- a/EGkFrame3d.h
+++ b/EGkFrame3d.h
@@ -41,6 +41,7 @@ class EGK_EXPORT Frame3d
       void Translate( const Vector3d& vtMove) ;
       bool Rotate( const Point3d& ptAx, const Vector3d& vtAx, double dCosAng, double dSinAng) ;
       bool Rotate( const Point3d& ptAx, const Vector3d& vtAx, double dAngRad) ;
+      bool PartialScale( const Frame3d& frRef, double dCoeffX, double dCoeffY, double dCoeffZ) ;
       // Scale non possibile (non previsti fattori di scala)
       // Mirror non possibile (cambia il senso destrorso in sinistrorso)
       bool Invert( void) ;