@article{02186891,
title = {Acyclic digraphs and eigenvalues of },
journal = {Journal of Integer Sequences [electronic only]},
volume = {7},
year = {2004},
zbl = {1064.05101},
language = {en},
url = {http://dml.mathdoc.fr/item/02186891}
}
McKay, Brendan D.; Oggier, Frédérique E.; Royle, Gordon F.; Sloane, N.J.A.; Wanless, Ian M.; Wilf, Herbert S. Acyclic digraphs and eigenvalues of . Journal of Integer Sequences [electronic only], Tome 7 (2004) . http://gdmltest.u-ga.fr/item/02186891/