Alternately, the information may be gathered as needed by polling {HEAD ~ each} of {TAIL ~ the appropriate connected communication sites}  
Alternately , the information may be gathered as needed by polling { HEAD ~ each } of { TAIL ~ the appropriate connected communication sites }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH