Giambattista Amati Edgardo Ambrosi Marco Bianchi Carlo Gaibisso Giorgio Gambosi Automatic Construction of an Opinion-Term Vocabulary for Ad Hoc Retrieval. 89-100 2008 ECIR http://dx.doi.org/10.1007/978-3-540-78646-7_11 conf/ecir/2008 db/conf/ecir/ecir2008.html#AmatiABGG08