C. Caetano, F. Bremond, and W. Schwartz.
" Skeleton Image Representation for 3D Action Recognition based on Tree Structure and Reference Joints", in <em>Anais da XXXII Conference on Graphics, Patterns and Images</em>, Rio de Janeiro, 2019, doi: <a href="https://doi.org/10.5753/sibgrapi.2019.9799">https://doi.org/10.5753/sibgrapi.2019.9799</a>.