This is particularly useful if the user of the machine does not have {HEAD ~ a user identifying information} suitable for {TAIL ~ authentication} 
suitable for
This is particularly useful if the user of the machine does not have { HEAD ~ a user identifying information } suitable for { TAIL ~ authentication }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL