Hong-Quang Nguyen J. Wenny Rahayu David Taniar Kinh Nguyen Mediation-Based XML Query Answerability. 1550-1558 2008 OTM Conferences (2) http://dx.doi.org/10.1007/978-3-540-88873-4_43 conf/otm/2008-2 db/conf/otm/otm2008-2.html#NguyenRTN08