Equation Icon  [ HaSbncd(x,y) = − Im ∇ax∇cyGFn (x,y)∇bx∇dyGFn (x,y) + ∇ax∇dyGFn(x, y)∇bx∇cyGFn (x,y ) ab e c x d − g (x)∇ x∇ yGFn(x, y)∇e∇ yGFn (x,y ) − gcd(y)∇a ∇eG (x,y )∇b ∇y G (x,y) x y Fn x e Fn + 1gab(x)gcd(y)∇e ∇f G (x,y)∇x ∇y G (x,y) 2 x y Fn e f Fn + 𝒦ab (2∇c G (x, y)∇d G (x, y) − gcd(y)∇e G (x,y)∇y G (x,y)) x ( y Fn y Fn y Fn e Fn ) + 𝒦cdy 2∇axGFn (x,y)∇bxGFn (x, y) − gab(x )∇exGFn (x,y)∇xeGFn (x,y) ab cd( 2 )] +2 𝒦 x 𝒦 y G Fn(x,y) , (46 )