{HEAD ~ A first fixed reflecting surface} of {TAIL ~ a parabolic group} reflecting surface can include a focus on the second focus of the first reflecting surface, and at least two second reflecting surface elements 
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{ HEAD ~ A first fixed reflecting surface } of { TAIL ~ a parabolic group } reflecting surface can include a focus on the second focus of the first reflecting surface , and at least two second reflecting surface elements
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH