Covering the edges of digraphs in $\mathcal{D}(3,3)$ and $\mathcal{D}(4,4)$ with directed cuts

Yandong Bai, Binlong Li, Shenggui Zhang

For nonnegative integers $k$ and $l$, let $\mathcal{D}(k,l)$ denote the family of digraphs in which every vertex has either indegree at most $k$ or outdegree at most $l$. In this p…