Martine Boonk Frances M. T. Brazier David de Groot Maarten van Stekelenburg Anja Oskamp Martijn Warnier Conditions for access and use of legal document retrieval web services. 37-41 2007 conf/icail/2007 ICAIL http://doi.acm.org/10.1145/1276318.1276325 db/conf/icail/icail2007.html#BoonkBGSOW07