Equation Icon  -- --- h(ρ,λ,μ ) = hbeta(ρ,λ) + δh(ρ,λ, μ), ( ) --- λ--- λ-- 2-- (3.92 ) δh(ρ,λ,μ ) = 2πs1(ϱ,t) + 2π s2(ϱ,t) + ...