“…To fix the Γ ρ rotations, we set some of the coefficients in J ρ to their (2, 2) values, taking, 14) and similarly for the pairs J 3 , J 4 and J 5 , J 6 . Finally, we fix the Σ a rotations by setting E a11 , E a22 , and E a33 to their (2,2) values.…”