{HEAD ~ A global time signal} from {TAIL ~ a global time reference} or common time source can be used to calculate a common view based clock offset between the two clocks 
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{ HEAD ~ A global time signal } from { TAIL ~ a global time reference } or common time source can be used to calculate a common view based clock offset between the two clocks
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL 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