XVII.Internationaler kongress fur reine und angewandte chemie. XVI.internatioaler kongress fur reine und angewandte chemie International congress of pure and applied chemistry. Internationaler Kongress für Reprographie Internationaler kongress uber felsmechanik xviii. internationaler congress fisita 1980. International Congress of Pure and Applied Chemistry International Congress of Puke and Applied Chemistry XVIth international congress of pure and applied chemistry =