“…As the functional a([ψ, ϕ, ω], [ψ,φ,ώ]) defined in the identity(9) with the propertya([ψ, ϕ, ω], [ψ,φ,ώ]) = a([ψ,φ,ω], [ψ,φ,ω]),then by using (71) together with the definition of the operator A in(34) and the formula (11), we geta([ψ, ϕ, ω], [ψ,φ,ώ]) = − Ω ψ 1 [ψ,φ,ω] + ϕ 2 [ψ,φ,ω] + ω 3 [ψ,φ,ω] dxdy…”