Equation Icon  --- -∂- -∂-- -∂-- 𝔐 = P ∂ζ + L ∂u = ∂ (uB) + L ∂u , (B.4 ) -- B -- B 𝔐 = P -∂-+ L -∂-- = ∂ (u ) + L -∂--, ∂ζ ∂uB B ∂uB ∂ 𝔏 = ----. ∂uB