Hamish Cunningham Norbert Fuhr Benno Stein Challenges in Document Mining (Dagstuhl Seminar 11171). 65-99 2011 1 Dagstuhl Reports 4 http://dx.doi.org/10.4230/DagRep.1.4.65 db/journals/dagstuhl-reports/dagstuhl-reports1.html#CunninghamFS11