CH 1990 FDC Bloc HELVETIA Geneve 90 - Format C6

CH 1990 FDC Bloc Nationale Briefmarkenausstellung in Genf "HELVETIA GENEVE 90" (SBK W72, Michel Bl.26) on ill. FDC Format C6 without address and off. first day cancellations 05.09.1990, no sale in this form by postal administration!