Commutative Weakly Distance-regular Digraphs of Valency 3 and Girth 2
YUE Meng-tian,LI Zeng-ti
Journal of Hebei University (Natural Science Edition) . 2008, (4): 346 -348 .  DOI: 10.3969/j.issn.1000-1565.2008.04.003