@article{DMTCS_2006_8_a11,
     author = {Nikolopoulos, Stavros D. and Palios, Leonidas},
     title = {Recognizing {HH-free,} {HHD-free,} and {Welsh-Powell} {Opposition} {Graphs}},
     journal = {Discrete mathematics & theoretical computer science},
     publisher = {mathdoc},
     volume = {8},
     year = {2006},
     doi = {10.46298/dmtcs.370},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.46298/dmtcs.370/}
}