P. G. K. Bertella, Y. K. Lopes, R. A. P. Oliveira, and A. C. Carniel.
"The Application of Spatial Approximations to Spatial Query Processing: A Systematic Review of Literature", in <em>Anais do XXXVI Simpósio Brasileiro de Bancos de Dados</em>, Rio de Janeiro, 2021, pp. 229-240, doi: <a href="https://doi.org/10.5753/sbbd.2021.17880">https://doi.org/10.5753/sbbd.2021.17880</a>.