Copyright © 2012 Ondrej Krejcar and Miroslav Mahdal. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Kromě případů, kde je uvedeno jinak, licence tohoto záznamu je Copyright © 2012 Ondrej Krejcar and Miroslav Mahdal. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.