Human rights — Freedom of expression — Limits on freedom of expression — Prohibitory injunction restraining applicant from repeating statements in consumer information bulletin — Conviction under German domestic legislation relating to unfair competition — Whether a justifiable interference with freedom of expression — Balancing of competing interests — States’ margin of appreciation not exceeded — Relevance of market economy — Relevance of publication based on isolated incident — European Convention on Human Rights, 1950, Article 10