About this article
Published Online: Nov 05, 2014
Page range: 73 - 91
Received: Oct 14, 2013
DOI: https://doi.org/10.2478/ausm-2014-0019
Keywords
© 2014
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.
Száz, Árpád
University of Debrecen Department of Mathematics H–4010Debrecen, Hungary