Stefania Castellani Aaron N. Kaplan Frédéric Roulland Jutta Willamowski Antonietta Grasso Creation and Maintenance of Query Expansion Rules. 819-830 2009 ICEIS http://dx.doi.org/10.1007/978-3-642-01347-8_68 conf/iceis/2009 db/conf/iceis/iceis2009.html#CastellaniKRWG09