Equation Icon  ∫ ˆωLd Ω = 0 if ℓ > 0, (B.26 ) ∫ ωLd Ω = 0 if ℓ is odd, (B.27 ) ∫ ω dΩ = 4πδ{i1i2 ...δiℓ−-1iℓ}-if ℓ is even, (B.28 ) L (ℓ + 1)!!