@techreport{MannMatthiessen90-twofunctions,
  author	= {Mann, William C. and Matthiessen, Christian M. I. M.},
  year		= {1990},
  title		= {Functions of Language in Two Frameworks},
  number	= {ISI/RR-90-290},
  note		= {(Presented at the 1987 International Systemic Workshop)},
  address	= {Los Angeles, California},
  institution	= {Information Sciences Institute},
}