Spectroscopy of La0.5Sr1.5MnO4 orbital ordering: a cluster many-body calculation A. Mirone, S. S. Dhesi and G. van der Laan Eur. Phys. J. B, 53 1 (2006) 23-28 Published online: 06 September 2006 DOI: 10.1140/epjb/e2006-00340-5