Victória Vargas, Eduardo Amorim, José André Brito, and Gustavo Semaan. 2021.
 A Study of Variants of the Silhouette Validation Index. In <em>Proceedings of the 4th Regional School on Informatics of Rio de Janeiro</em>, November 23, 2021, Online, Brasil. SBC, Porto Alegre, Brasil, 123-126. DOI: <a href="https://doi.org/10.5753/eri-rj.2021.18784">https://doi.org/10.5753/eri-rj.2021.18784</a>.