Relativistic coupled cluster method - Excitation and ionization energies of Sr and Yb atom Malaya K. Nayak and Rajat K. Chaudhuri Eur. Phys. J. D, 37 2 (2006) 171-176 Published online: 25 October 2005 DOI: 10.1140/epjd/e2005-00279-1