Dietmar Jannach Markus Zanker Markus Jessenitschnig Oskar Seidler Developing a Conversational Travel Advisor with ADVISOR SUITE. 43-52 2007 ENTER http://dx.doi.org/10.1007/978-3-211-69566-1_5 conf/enter/2007 db/conf/enter/enter2007.html#JannachZJS07