The decays of $B_c$ meson to P-wave charmonium $\chi_c(h_c)$ and to   leptons with gluon bremsstrahlung
  Theoretical computations on the decays of $B_c$ meson to $P$-wave charmonium $\chi_c$ or $h_c$ with some particle(s) else and on the decays of $B_c$ meson to leptons with gluon bremsstrahlung, and the results as well are outlined. 
Chao-Hsi Chang (Zhao-Xi Chang)