@article{DMGT_2014_34_1_a13,
     author = {Hell, Pavol and Hern\'andez-Cruz, C\'esar},
     title = {On the {Complexity} of the {3-Kernel} {Problem} in {Some} {Classes} of {Digraphs}},
     journal = {Discussiones Mathematicae. Graph Theory},
     pages = {167--185},
     publisher = {mathdoc},
     volume = {34},
     number = {1},
     year = {2014},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DMGT_2014_34_1_a13/}
}