  We emphasize the importance of experiments with voltage dependent field
emission energy distribution analysis in carbon nanosheets. Our analysis shows
the crucial influence of the band structure on the energy distribution of field
emitted electrons in few-layer graphene. In addition to the main peak we found
characteristic sub-peaks in the energy distribution. Their positions strongly
depend on the number of layers and the inter-layer interaction. The discovery
of these peaks in field emission experiments from carbon nanosheets would be a
clear manifestation of the quantum size effect in these new materials.
