@incollection{Torre97TheManyFaces,
author = {van der Torre, L. and Tan, Y},
booktitle = {Defeasible Deontic Logic, volume 263 of Synthese Library},
date-modified = {2011-12-20 17:12:38 +0100},
editor = {Nute, D.},
pages = {79-121},
publisher = {Kluwer},
title = {The many faces of defeasibility in defeasible deontic logic},
url = {http://icr.uni.lu/leonvandertorre/papers/ddl97.ps.Z},
year = {1997},
bdsk-url-1 = {http://icr.uni.lu/leonvandertorre/papers/ddl97.ps.Z}
}