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1. The informative signs referred to in Articles 15 to 19 of this Convention shall be set up where the competent authorities consider it advisable. The other informative signs shall be set up, with due regard for the requirements of Article 6, paragraph 1, only where the competent authorities consider it essential; in particular, signs F, 2 to F, 7 shall be set up only on roads on which facilities for emergency repairs, refuelling, accommodation and refreshments are rare.
2. Informative signs may be repeated. An additional panel placed below the sign may show the distance between the sign and the point which it indicates; this distance may also be inscribed on the lower part of the sign itself.