Judgment of the Court of 26 September 2000 in Case C-175/99 (reference for a preliminary ruling from the Conseil de Prud'hommes de Metz): Didier Mayeur v Association Promotion de l'Information Messine (APIM) (Maintenance of workers' rights in the event of transfer of an undertaking — Transfer to a municipality of an activity previously carried out, in the interests of that municipality, by a legal person established under private law)