46Once the authorities of one Member State have issued a driving licence in accordance with Article 1(1) of Directive 91/439, the other Member States are not entitled to investigate whether the conditions for issue laid down by that directive have been met. The possession of a driving licence issued by one Member State has to be regarded as constituting proof that on the day on which that licence was issued, its holder satisfied those conditions (see, inter alia, Schwarz, paragraph 77, and Grasser, paragraph 21).