@Unpublished{Riv83x,
  author =       { Ronald L. Rivest },
  title =        { What is the purpose and structure of intelligence? },
  note =         { (Unpublished draft.) },
  date =         { 1983-08-16 },
  OPTyear =      { 1983 },
  OPTmonth =     { August 16, },
}