European evidence based consensus on the diagnosis and management of Crohn's disease: current management. - Travis,S.P.; Stange,E.F.; Lemann,M.; Oresland,T.; Chowers,Y.; Forbes,A.; D'Haens,G.; Kitis,G.; Cortot,A.; Prantera,C.; Marteau,P.; Colombel,J.F.; et al. (Gut, 2006)