@MISC{ROUGHS_2.MIZ,
  AUTHOR = {Grabowski, Adam},
  TITLE = {Relational Formal Characterization of Rough Sets},
  SECTION1 = {Preliminaries},
  SECTION2 = {Missing Ordinary Properties of Binary Relations},
  SECTION3 = {Approximations Revisited},
  SECTION4 = {General Properties of Approximations},
  SECTION5 = {Auxiliary Operation on Approximation Operators},
  SECTION6 = {Towards Topological Models of Rough Sets},
  SECTION7 = {Formalization of Zhu's Paper},
  DAY = {17},
  MONTH = {January},
  YEAR = {2013},
  ADDRESS1 = {Institute of Informatics\\University of Bia{\l}ystok\\Akademicka 2, 15-267 Bia{\l}ystok\\Poland},
  SUMMARY = {Rough sets, developed by Pawlak, are important tool to
  describe situation of incomplete or partially unknown information.
  In this article, which is essentially the continuation of
  \cite{ROUGHS_1.ABS}, we try to give the characterization of
  approximation operators in terms of ordinary properties of
  underlying relations (some of them, as serial and mediate
  relations, were not available in the MML).
  Here we drop the classical equivalence- and tolerance-based models
  of rough sets trying to formalize some parts of
  \cite{Zhu:2007}.}}

@ARTICLE{Zhu:2007,
 AUTHOR = {Zhu, William},
 TITLE = {Generalized Rough Sets Based on Relations},
 JOURNAL = {Information Sciences},
 VOLUME = 177,
 PAGES = {4997--5011},
 YEAR=2007}





