In decays involving two vector mesons, one can distinguish among the states in which meson polarizations are both longitudinal ($\mathit L$), or both are transverse and parallel ($\parallel$), or perpendicular ($\perp$) to each other with the parameters $\Gamma _{L}/\Gamma $, $\Gamma _{\perp}/\Gamma $, and the relative phases $\phi _{\parallel}$ and $\phi _{\perp}$. In decays involving two tensor mesons, the transverse polarization states are described by parameters $\Gamma _{\parallel1}$, $\Gamma _{\parallel2}$, $\Gamma _{\perp1}$, $\Gamma _{\perp2}$ and their relative phases $\phi _{\parallel1}$, $\phi _{\parallel2}$, $\phi _{\perp1}$, $\phi _{\perp2}$. See also the review on “Polarization in ${{\mathit B}}$ Decays.''