Gary L. Ebert, Sebastian Egner, Henk D. L. Hollmann, Qing Xiang. A Four-Class Association Scheme. Journal of Combinatorial Theory, Series A, 96(1):180-191, 2001. [doi]
@article{EbertEHX01,
title = {A Four-Class Association Scheme},
author = {Gary L. Ebert and Sebastian Egner and Henk D. L. Hollmann and Qing Xiang},
year = {2001},
doi = {10.1006/jcta.2001.3183},
url = {http://dx.doi.org/10.1006/jcta.2001.3183},
researchr = {https://researchr.org/publication/EbertEHX01},
cites = {0},
citedby = {0},
journal = {Journal of Combinatorial Theory, Series A},
volume = {96},
number = {1},
pages = {180-191},
}