Search Event Frames referencing a specific element

SELECT ef.Name as EF_Name, ef.starttime, ef.endtime, e.name
FROM EventFrame.eventframe ef
INNER JOIN Eventframe.EventFrameReferencedElement efr
ON efr.EventframeID=ef.ID
INNER JOIN Asset.Element e
ON e.ID=efr.ElementID
WHERE e.name='Reactor R12' AND ef.endtime < '6-jun-2012' AND ef.HasChildren=FALSE
ORDER BY 1;

Returns all event frames that reference a specific element, have no children and end before a specific date.