+ Cartesian products of Cartesian products work::
+
+ sage: J1 = JordanSpinEJA(1)
+ sage: J2 = JordanSpinEJA(1)
+ sage: J3 = JordanSpinEJA(1)
+ sage: J = cartesian_product([J1,cartesian_product([J2,J3])])
+ sage: J.multiplication_table()
+ +--------------++---------+--------------+--------------+
+ | * || e(0, 0) | e(1, (0, 0)) | e(1, (1, 0)) |
+ +==============++=========+==============+==============+
+ | e(0, 0) || e(0, 0) | 0 | 0 |
+ +--------------++---------+--------------+--------------+
+ | e(1, (0, 0)) || 0 | e(1, (0, 0)) | 0 |
+ +--------------++---------+--------------+--------------+
+ | e(1, (1, 0)) || 0 | 0 | e(1, (1, 0)) |
+ +--------------++---------+--------------+--------------+
+ sage: HadamardEJA(3).multiplication_table()
+ +----++----+----+----+
+ | * || e0 | e1 | e2 |
+ +====++====+====+====+
+ | e0 || e0 | 0 | 0 |
+ +----++----+----+----+
+ | e1 || 0 | e1 | 0 |
+ +----++----+----+----+
+ | e2 || 0 | 0 | e2 |
+ +----++----+----+----+
+