@incollection{Ure-71,
  author	= {Ure, Jean},
  editor	= {Parren, G. and Trim, J.},
  year		= {1971},
  title		= {Lexical density and register differentiation},
  booktitle	= {Applications of Linguistics},
  publisher	= {Cambridge University Press},
  address	= {Cambridge}
}