Thor Johnson, Neil Robertson, Paul D. Seymour, Robin Thomas. Directed Tree-Width. Journal of Combinatorial Theory, Series A, 82(1):138-154, 2001. [doi]
@article{JohnsonRST01,
title = {Directed Tree-Width},
author = {Thor Johnson and Neil Robertson and Paul D. Seymour and Robin Thomas},
year = {2001},
doi = {10.1006/jctb.2000.2031},
url = {http://dx.doi.org/10.1006/jctb.2000.2031},
researchr = {https://researchr.org/publication/JohnsonRST01},
cites = {0},
citedby = {0},
journal = {Journal of Combinatorial Theory, Series A},
volume = {82},
number = {1},
pages = {138-154},
}