K⁡(z,ζ)=k⁢Ai⁡(z+ζ2)+k24⁢∫z∞∫z∞K⁡(z,s)⁢Ai⁡(s+t2)⁢Ai⁡(t+ζ2)⁢ⅆ⁡s⁢ⅆ⁡t,