//Returns top label of this function's history tree
Standard_EXPORT TDF_Label GetHistoryEntry (const Standard_Boolean create = Standard_True);
//Returns history label, corresponding to the label,
//on which a reference on argument is stored
Standard_EXPORT TDF_Label GetArgumentHistoryEntry (const TDF_Label& theArgumentRefEntry,
//Returns top label of this function's history tree
Standard_EXPORT TDF_Label GetHistoryEntry (const Standard_Boolean create = Standard_True);
//Returns history label, corresponding to the label,
//on which a reference on argument is stored
Standard_EXPORT TDF_Label GetArgumentHistoryEntry (const TDF_Label& theArgumentRefEntry,