Excited states in quantum chemistry : theoretical and experimental aspects of the electronic structure and properties of the excited states in atoms, molecules and solids: proceedings of the NATO Advanced Study Institute held at Kos, Greece, June 4-18, 1978 - Νικολαίδης, Κλεάνθης Α.; Beck, Donald R. (NATO advanced study institutes series. Series C, Mathematical and physical sciences ;, 1979)