Nonexistence of exceptional imprimitive Q-polynomial association schemes with six classes

@article{Tanaka2011NonexistenceOE,
  title={Nonexistence of exceptional imprimitive Q-polynomial association schemes with six classes},
  author={Hajime Tanaka and Rie Tanaka},
  journal={Eur. J. Comb.},
  year={2011},
  volume={32},
  pages={155-161}
}
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