@article{1998-Wondergem-Nesting,
  author		= "Wondergem, B.C.M. and Bommel, P. van and Weide, Th.P. van der",
  title			= "{Nesting and Defoliation of Index Expressions for Information Retrieval}",
  journal		= "Knowledge and Information Systems",
  volume		= "2",
  year			= "1998",
  code			= "basvg.012 icis.CSI-R9817",
  research_group	= "iris",
  pages			= "33--52",
  class			= "Journal"
}