4 Article 15 – The authors of pseudonymous and anonymous works shall enjoy in those works the rights provided for in Article 1. In exercising these rights they shall be represented by the original editor or publisher, until such time as they reveal their identity and have proven their authorship. The declaration provided for in the preceding paragraph may be made by testamentary means, provided any rights previously acquired by third parties are reserved. The provisions of the second and third paragraphs shall not be applicable where the pseudonym adopted by the author leaves no doubt as to his identity. Article 16 – The natural person or persons responsible for the intellectual creation of an audiovisual work shall be regarded as the author or authors of that work. In the absence of proof to the contrary, the following shall be regarded as the co-authors of a collaboratively produced audiovisual work: 1. The author of the screenplay; 2. The author of the adaptation; 3. The author of the spoken text; 4. The author of the musical compositions with or without words specially created for the work; 5. The director. Where an audiovisual work is taken from a pre-existing and still protected work or screenplay, the authors of the original work shall be assimilated to the authors of the new work. Article 17 – The natural person or persons responsible for the intellectual creation of a radiophonic work shall be deemed to be the author or authors of that work. The provisions of the final paragraph of Article 16 and those of Article 26 shall be applicable by analogy to radiophonic works. Article 18 – The author of the musical compositions with or without words specially created for the work and the writer of the words shall be deemed to be the authors of a completed dramatic or dramatico-musical work. The provisions of the final paragraph of Article 16 and those of Article 26 shall be applicable by analogy to dramatic and dramatico-musical works. Article 19 – Save as otherwise provided, copyright in software program created by one or more employees in the performance of their duties shall be enjoyed by the employer. Any challenge to the application of this article shall be brought before the civil court in the place of the registered office of the employer. The provisions of the first paragraph of this article shall also be applicable to agents of the State, of the public authorities and of public institutions of an administrative nature.