When step 37 is reached, ambiguity should lie only in {HEAD ~ the presence} of {TAIL ~ a tone}, or a `stationary` voiced speech 
of
When step 37 is reached , ambiguity should lie only in { HEAD ~ the presence } of { TAIL ~ a tone } , or a ` stationary ` voiced speech
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH