{HEAD ~ The user}, vendor, manufacturer and other supplier may maintain {TAIL ~ databases} housed on the central computers 
{ HEAD ~ The user } , vendor , manufacturer and other supplier may maintain { TAIL ~ databases } housed on the central computers
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH