Dielectrically confined excitons and polaritons in natural superlattices - perovskite lead iodide semiconductors N.A. GIPPIUS, T. ISHIHARA, L.V KELDYSH, E.A. MULJAROV et S.G. TIKHODEEV Le Journal de Physique IV, 03 C5 (1993) C5-437-C5-440 DOI: 10.1051/jp4:1993594