[sv-bc] Covergroup Clocking Event?

Hi, All -

A couple of us were trying to determine if a covergroup clocking event
could be a multi-event statement, such as:

covergroup cg1 @(a or b or posedge c); ...

A quick search of the LRM did not show any similar examples, but we also
did not find any specific prohibitions listed anywhere. Does anyone have
and answer or could anyone point us to the section that describes the
prohibition?

Thanks - Cliff