@Unpublished{DJDHughes:freestar,
  author    =  {Hughes, Dominic J.D.},
  title     =  {Simple free star-autonomous categories and full coherence},
  year      =  {2005},
  month     =  {June},
  note      =  {Draft, archived as math.CT/0506521 at arXiv.org.}  
}