@article{article, title = {{Lehman's Theorem and the Directed Steiner Tree Problem}}, publisher = {{Society for Industrial & Applied Mathematics (SIAM)}}, url = {{http://dx.doi.org/10.1137/15m1007185 }}, year = {{2016}}, month = {{1}}, author = {{Abdi A and Feldmann AE and Guenin B and Könemann J and Sanità L}}, doi = {{10.1137/15m1007185}}, volume = {{30}}, journal = {{SIAM Journal on Discrete Mathematics}}, issue = {{1}}, pages = {{141-153}}, note = {{Accessed on 2024/12/23}}}