@INPROCEEDINGS{AntoyBrasselHanus03PPDP,
 author = {Sergio Antoy and Bernd Brassel and Michael Hanus},
 title = {Conditional narrowing without conditions},
 booktitle = {Proceedings of the 5th ACM SIGPLAN international conference on Principles and practice of declaritive programming},
 year = {2003},
 isbn = {1-58113-705-2},
 pages = {20--31},
 location = {Uppsala, Sweden},
 doi = {http://doi.acm.org/10.1145/888251.888255},
 publisher = {ACM Press},
 }