@article{DBLP:journals/logcom/DelgrandeS05,
  author = {Delgrande, James P. and Schaub, Torsten},
  title = {Expressing Default Logic Variants in Default Logic},
  journal = {J. Log. Comput.},
  volume = {15},
  number = {5},
  pages = {593--621},
  year = {2005}
}