Exact solution Dirac equation for an energy-dependent potential H. Hassanabadi, E. Maghsoodi, R. Oudi, S. Zarrinkamar and H. Rahimov Eur. Phys. J. Plus, 127 10 (2012) 120 Published online: 04 October 2012 DOI: 10.1140/epjp/i2012-12120-1