@InProceedings{CKM15,
author={Thomas  Caridroit and S├ębastien  Konieczny and Pierre  Marquis},
title= {Contraction in Propositional Logic},
booktitle = {Thirteenth European Conference on Symbolic and Quantitative Approaches to Reasoning with Uncertainty (ECSQARU'15)} ,
pages = {186-196},
year= {2015}
}