@incollection{Martin91-encyc,
  author	= {Martin, James R.},
  editor	= {Bright, W.},
  title		= {Systemic grammar},
  booktitle	= {The Oxford International Encyclopedia of Linguistic},
  address	= {London},
  volume	= {IV},
  publisher	= {Oxford University Press},
  year		= {1991},
  pages		= {120--122},
  note		= {(revised 2001)}
}