  The low energy effective field model for the multilayer graphene (at ABC
stacking) is considered. We calculate the effective action in the presence of
constant external magnetic field $B$ (normal to the graphene sheet). We also
calculate the first two corrections to this effective action caused by the
in-plane electric field $E$ at $E/B \ll 1$ and discuss the magnetoelectric
effect. In addition, we calculate the imaginary part of the effective action in
the presence of constant electric field $E$ and the lowest order correction to
it due to the magnetic field ($B/E \ll 1$).
