About this article
Published Online: Dec 31, 2018
Page range: 48 - 52
DOI: https://doi.org/10.2478/disp-1997-0004
© 2019 Pedro Galvão, published by Sciendo
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.
Pedro Galvão
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