Caroline Devred Sylvie Doutre Dialectical Proof Theories for the Credulous Prudent Preferred Semantics of Argumentation. 271-282 2007 conf/ecsqaru/2007 ECSQARU http://dx.doi.org/10.1007/978-3-540-75256-1_26 db/conf/ecsqaru/ecsqaru2007.html#DevredD07