@INPROCEEDINGS { Rsds3801,
author = {Yao, Yiyu and Li, Xining and Lin, Tsau Young and Liu, Qing}, 
title = {Representation and Classification of Rough-Set Models}, 
booktitle = {Soft Computing}, 
conference = {International Workshop on Rough Sets and Soft Computing}, 
pages = {44--47}, 
publisher = {The Society for Computer Simulation}, 
address = {San Diego, U.S.A.}, 
month = {November}, 
year = 1994, 
editor = {Lin, Tsau Young and Wildberger, A.M.}, 
isbn = {1-56555-077-3}, 
abstract = {The rough-set theory is interpreted as an extension of set theory with additional set-theoretic operators defined by a binary relation on the universe. Based on properties satisfied by a binary relation, classes of rough-set models may be derived. Each rough-set model represents the set-theoretic counter-part of a modal logic system which is an extension of propositional logic with modal operators. Classification of rough-set models can be done in the same manner as classifying modal logic systems.}, 
keywords = {modal logic, rough sets, uncertain reasoning, }, 
}