@INPROCEEDINGS { Rsds4899,
author = {Liu, Gui-Long}, 
title = {Lattice Structures of Rough Fuzzy Sets}, 
booktitle = {Rough Sets, Fuzzy Sets, Data Mining, and Granular Computing}, 
series =  = {Lecture Notes in Artificial Intelligence}, 
volume = 5908, 
pages = {253--260}, 
publisher = {Springer-Verlag}, 
address = {Heidelberg - Berlin, Germany}, 
year = 2009, 
editor = {Sakai, Hiroshi and Chakraborty, Mihir Kumar and Hassanien, Aboul Ella and Slezak, Dominik and Zhu, William}, 
url = {http://www.springerlink.com/content/r06323721k31/?p=7e2c1f1fe7ff42eb9b862fbed1bfd7d8&pi=19}, 
issn = {0302-9743}, 
isbn = {978-3-642-10645-3}, 
abstract = {This paper studies lattice structure of the family of rough fuzzy sets in a given approximation space. Our result is an extension of standard rough sets. Starting with the definition of rough fuzzy sets, the union, intersection and pseudocomplementation operations are generalized. Then it is proved that the above family with these operations is a distributive lattice. This paper also gives the characterization of borderline region of rough fuzzy sets.}, 
keywords = {rough sets, fuzzy sets, rough fuzzy sets, lower approximations, upper approximations, lattices, }, 
}