L. Viana and M. Campêlo.
" The Least-Dependency Constrained Spanning Tree Problem", in <em>Proceedings of the 2nd Theory of Computation Meeting</em>, São Paulo, 2017, pp. 53-56, doi: <a href="https://doi.org/10.5753/etc.2017.3190">https://doi.org/10.5753/etc.2017.3190</a>.