@article{DBLP:journals/jct/GodsilM95,
author = {C. D. Godsil and
William J. Martin},
title = {Quotients of Association Schemes},
journal = {J. Comb. Theory, Ser. A},
volume = {69},
number = {2},
year = {1995},
pages = {185-199},
bibsource = {DBLP, http://dblp.uni-trier.de}
}