  Dynamics of quasi-particles in graphene with an impurity and a sharp edge is
considered with the kp perturbation theory that allows an unified approach
without usage of any models. Dirac and Weyl equations are derived by the
above-mentioned method. The wave function and its envelope function together
with the scattering amplitude are found in the Born approximation. The wave
functions are shown to be a superposition of virtual Bloch functions which
exponential decay outward from the impurity and the edge. At distances much
greater that the atomic spacing the wave functions are explicitly presented.
Green's functions for Schr\"odinger and Dirac equations are derived as well.
Boundary conditions for the Dirac equation for graphene with a sharp edge are
also derived.
