@incollection{Butler87,
  author	= {Butler, Christopher S.},
  editor	= {Halliday, Michael A. K. and Fawcett, Robin P.},
  year		= {1987},
  title		= {Communicative function and semantics},
  booktitle	= {New Developments in Systemic Linguistics. Volume 1},
  publisher	= {Frances Pinter},
  address	= {London}
}