diff --git a/EXE_GdbPartLayers.cpp b/EXE_GdbPartLayers.cpp
index 2cb6633..b6ae154 100644
--- a/EXE_GdbPartLayers.cpp
+++ b/EXE_GdbPartLayers.cpp
@@ -922,8 +922,10 @@ ExeIsDuplo( int nDupId)
    if ( nDuploBaseId == GDB_ID_NULL)
       return false ;
   // Verifico sia un duplicato (gruppo sotto quello dei duplicati con riferimento a originale)
+   int nBaseId ;
    if ( pGeomDB->GetGdbType( nDupId) == GDB_TY_GROUP  &&
-        pGeomDB->GetParentId( nDupId) == nDuploBaseId  &&
+        ( pGeomDB->GetParentId( nDupId) == nDuploBaseId  ||
+          ( pGeomDB->GetInfo( nDupId, GDB_SI_BASE, nBaseId)  &&  pGeomDB->GetParentId( nBaseId) == nDuploBaseId))  &&
         pGeomDB->ExistsInfo( nDupId, GDB_SI_DUPSOU))
       return true ;
    else