Ana Casali Lluis Godo Carles Sierra Validation and Experimentation of a Tourism Recommender Agent based on a Graded BDI Model. 41-50 2008 CCIA http://dx.doi.org/10.3233/978-1-58603-925-7-41 conf/ccia/2008 db/conf/ccia/ccia2008.html#CasaliGS08