Fourier transform of the operator $\log^2(-\Delta)u$

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I need to calculate the Fourier transform of the operator $\log^2(-\Delta)u $, but I don't know any property that can help me. I know that the transform of $\log(-\Delta)u $ is $\log(|\xi|^2)\hat{u}(t)$. Something tells me the transformation I want is $\log^2(|\xi|^2)\hat{u}(t)$, but I don't know how to proceed.