  The dilepton invariant mass spectra and integrated branching ratios of the
single and double Dalitz decays $\mathcal{P}\to\ell^{+}\ell^{-}\gamma$ and
$\mathcal{P}\to\ell^{+}\ell^{-}\ell^{+}\ell^{-}$ ($\mathcal{P}=\pi^{0}, \eta,
\eta^{\prime}$; $\ell=e$ or $\mu$) are predicted by means of a data-driven
approach based on the use of rational approximants applied to $\pi^{0}, \eta$
and $\eta^{\prime}$ transition form factor experimental data in the space-like
region.
