1. See e.g. L.J. de Jongh, J.A.O. de Aguiar, H.B. Brom, G. Longoni, J.M. van Ruitenbeek, G. Schmid, H.H.A. Smit, M.P.J. van Staveren and R.C. Thiel, Z. Phys. D12 (1989) 445
2. L.J. de Jongh, H.B. Brom, J.M. van Ruitenbeek, R.C. Thiel, G. Schmid, G. Longoni, A. Ceriotti, R.E. Benfield and R. Zanoni in: "Cluster models for surface and bulk phenomena", eds. G. Pacchioni and P.G. Bagus, Plenum (1991) ( NATO ASI Series B, Physics).
3. G. Longoni, A. Ceriotti, M. Marchionna and G. Piro, in: “Surface Organometallic Chemistry: Molecular Approaches to Surface Catalysis”,eds. J.M. Basset et al., Kluwer (1988) p.157 (and references in this review).
4. G. Schmid, Polyhedron 7 (1988) 2321
5. Endeavour, New Series 14 (1990) 172