TODO

   1 1. Add CartesianProductEJA.
   2
   3 2. Check the axioms in the constructor when check != False?
   4
   5 3. Add references and start citing them.
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   7 4. Implement the octonion simple EJA.
   8
   9 5. Factor out the unit-norm basis (and operator symmetry) tests once
  10    all of the algebras pass.