{HEAD ~ This configuration} is established by {TAIL ~ means} of the confocal paraboloids 104 and 140 
is established by
{ HEAD ~ This configuration } is established by { TAIL ~ means } of the confocal paraboloids 104 and 140
HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH