@inproceedings {Risch96b,
author = {V. Risch},
title = {Cumulative Default Theories vs Non-cumulative Default Logics},
booktitle = {Proceedings of the 6th International Workshop on Non-Monotonic Reasoning, NMR'96},
address = {Timberline, Oregon, USA},
month = {june 9 -- 11},
year = {1996},
pages = {116--122}
}