On knot-free vertex deletion: Fine-grained parameterized complexity analysis of a deadlock resolution graph problem

ADA Carneiro, F Protti, U dos Santos Souza - Theoretical Computer …, 2022 - Elsevier
A knot in a directed graph G is a strongly connected subgraph Q of G with size at least two,
such that no vertex in V (Q) is an in-neighbor of a vertex in V (G)∖ V (Q). Knots are important …

Width parameterizations for knot-free vertex deletion on digraphs

S Bessy, M Bougeret, ADA Carneiro, F Protti… - arXiv preprint arXiv …, 2019 - arxiv.org
A knot in a directed graph $ G $ is a strongly connected subgraph $ Q $ of $ G $ with at least
two vertices, such that no vertex in $ V (Q) $ is an in-neighbor of a vertex in $ V (G)\setminus …