@inproceedings{DBLP:conf/ecsqaru/DelgrandeS01, title = {How to Reason Credulously and Skeptically within a Single Extension}, author = {Delgrande, James P. and Schaub, Torsten}, booktitle = {{ECSQARU}}, pages = {592--603}, publisher = {Springer}, series = {Lecture Notes in Computer Science}, volume = {2143}, year = {2001} }