@article{vera_weintraub_koenig_bravo_guignard_barahona_2003,  title={A lagrangian relaxation approach for a machinery location problem in forest harvesting},  volume={23},  ISSN={0101-7438},  url={https://doi.org/10.1590/S0101-74382003000100009},  DOI={10.1590/S0101-74382003000100009},  number={1},  journal={Pesquisa Operacional},  publisher={Sociedade Brasileira de Pesquisa Operacional},  author={Vera, Jorge R. and Weintraub, Andrés and Koenig, Manfred and Bravo, Gaston and Guignard, Monique and Barahona, Francisco},  year={2003},  month={Jan},  pages={111–128} }