@article{v013a020, author = {Shepherd, F. Bruce and Vetta, Adrian R.}, title = {The Inapproximability of Maximum Single-Sink Unsplittable, Priority and Confluent Flow Problems}, year = {2017}, pages = {1--25}, doi = {10.4086/toc.2017.v013a020}, publisher = {Theory of Computing}, journal = {Theory of Computing}, volume = {13}, number = {20}, URL = {https://theoryofcomputing.org/articles/v013a020}, }