@article{10_37236_11275,
     author = {Raphael Yuster},
     title = {The covering threshold of a directed acyclic graph by directed acyclic subgraphs},
     journal = {The electronic journal of combinatorics},
     year = {2022},
     volume = {29},
     number = {4},
     doi = {10.37236/11275},
     zbl = {1506.05178},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/11275/}
}