\[\mathsf{P}^{-m}_{\nu}\left(x\right)=\left(1-x^{2}\right)^{-m/2}\int_{x}^{1}\!%
\dots\!\int_{x}^{1}\mathsf{P}_{\nu}\left(x\right)\left(\!\,\mathrm{d}x\right)^%
{m}.\]