Erreur pour accéder sur un signet

Sub AtteindreSignet 
Dim Doc As Object , oCC As Object , oCursor As Object 
Dim BookMark As Object 

Doc = ThisComponent 
oCC = Doc.getCurrentController() 
  db=Doc.BookMarks
'Définit le signet cible  
BookMark = Doc.BookMarks.GetByName("emis") 

oCursor = Doc.text.createTextCursorByRange(BookMark.Anchor)  
oCC.Select(oCursor)  

End Sub