Conjugated oligomers, polymers and dendrimers : from polyacetylene to DNA : proceedings of the Fourth Francqui Colloquium, 21-23 October 1998, Brussels - Bredas, Jean-Luc (Bibliotheque scientifique Francqui = Francqui scientific library = Wissenschaftliche Bibliothek francqui = Wetenschappelijke bibliotheek Francqui ;, 1999)