@book{rijsbergen79information,
  address = {London},
  author = {van Rijsbergen, C. J.},
  edition = 2,
  interhash = {0edccdac9af024f458911b82f61686ab},
  intrahash = {b53893655b48140d4310a848dbf204d3},
  publisher = {Butterworths},
  title = {Information retrieval},
  url = {http://www.dcs.gla.ac.uk/Keith/Preface.html},
  year = 1979
}