@article{TangCHGC06,
 author = {Thanh Tang and Nick Craswell and David Hawking and Kathleen Griffiths and Helen Christensen},
 title = {Quality and Relevance of Domain-specific Search: A Case Study 
          in Mental Health},
 journal = {Information Retrieval},
 year = {2006},
volume = {9},
number = {2},
pages = {207--225},
 note = {\url{http://david-hawking.net/pubs/tang_domainspec.pdf}}
}