"Public authorities also have certain positive obligations. They must submit lawfully presented candidatures to the citizens’ votes. The presentation of specific candidatures may be prohibited only in exceptional circumstances, where necessitated by a greater public interest. Public authorities must also give the electorate access to lists and candidates standing for election by means, for instance, of appropriate billposting. The information in question must also be available in the languages of national minorities, at least where they make up a certain percentage of the population. Voters’ freedom to form an opinion may also be infringed by individuals, for example when they attempt to buy votes, a practice which the state is obliged to prevent or punish effectively. "