Nadine Weber Raiko Eckstein Andreas Henrich Searching Multiple Artifacts: A Comprehensive Framework for Complex Search Situations. 251-262 2009 FQAS http://dx.doi.org/10.1007/978-3-642-04957-6_22 conf/fqas/2009 db/conf/fqas/fqas2009.html#WeberEH09