@MISC{TAXONOM2.MIZ,
  AUTHOR = {Giero, Mariusz},
  TITLE = {Hierarchies and Classifications of Sets},
  NOTE = {This work has been partially supported by the European Community TYPES grant IST-1999-29001
and CALCULEMUS grant HPRN-CT-2000-00102.},
  ACKNOWLEDGEMENT = {I would like to thank Prof. Andrzej Trybulec for his help in the preparation
                  of this article.},
  SECTION1 = {Tree and Classification of a Set},
  SECTION2 = {The Hierarchy of a Set},
  SECTION3 = {Some Properties of Partitions, Hierarchies and Classifications of Sets},
  DAY = {28},
  MONTH = {December},
  YEAR = {2001},
  ADDRESS1 = {University of Bia{\l}ystok},
  SUMMARY = {This article is a continuation of \cite{TAXONOM1.ABS} article. Further properties
         of classification of sets are proved. The notion of hierarchy of a set
         is introduced. Properties of partitions and hierarchies are shown. The main
         theorem says that for each hierarchy there exists a classification
         which union equals to the considered hierarchy.}}

