Reg : CATIA Feature show-up in HistoryTree/ ModelTree

Hi all,
This API creating Catia Feature ExtractIsoParametricCurve. But, I could not able to show it in the Catia Model Tree.
//Code
CATCurve *ipParametricCurve 
ipParametricCurve = mySurface->ExtractIsoParametricCurve(isoParU, surParamPt, pGeomFactory);

ipParametricCurve Feature to shown in History Tree. For showing in CATIA History Tree, we need to use CSpecObj_var->InsertInProceduralView();

CSpecObj->Update();
But, I'm not able to convert ipParametricCurve (CATCurve) to CatiSpecObject. Can anybody help me please..