2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 | 2014 | 2013 | 2012 | 2011 | 2010 | 2009 | 2008
Authors: D.P. Menezes, C. ProvidĂȘncia,
Ref.: Braz. J. Phys. 34, 724-727 (2004)