Hello, we are preparing an exhibition on the topic of Czechoslovakia. legions and the establishment of the republic. We need to get a lot of period photos. Most of them can be found on the websites of various military history clubs or other sites. Unfortunately, it happens that no one is depreciating or a page has no contact, or the page was last updated ten years ago. I would like to ask you if I can use the photos without the consent of the author of the site (of course, the source would be listed) according to these points in copyright law. § 2 (1) The subject of copyright is a literary work and other artistic and scientific work, which is a unique result of the author's creative activity and is expressed in any objectively perceptible form, including electronic, permanent or temporary, regardless of its scope, purpose or meaning (hereinafter referred to as "the work"). The work is mainly a verbal work expressed in speech or writing, a musical work, a dramatic work and a musical dramatic work, a choreographic and pantomime work, a photographic work and a work expressed by a photograph-like process, an audiovisual work such as a cinematographic work, a work of art such as a painting , graphic and sculptural, architectural work including urban work, work of applied art and cartographic work. § 11 (4) The author may not waive personal rights; these rights are non-transferable and expire upon the author's death. This is without prejudice to the provisions of paragraph 5. § 11 (5) After the death of the author, no one may personalize his authorship of the work, the work may be used only in a way that does not reduce its value and, if usual, the author of the work must be mentioned, unless the work is anonymous. Protection can be claimed by any of the persons close to the author, 1a) they have this right, even if the term of the copyright has expired. This protection can always be claimed by a legal entity associating authors or the relevant collective administrator pursuant to this Act (Section 97). Most of the photos today do not have a known author and come from the albums of the legionnaires. The photos were not taken by them, they just got them in memory, they are often repeated in albums. However, it is often written on the website that if I use photos without their consent, I can be prosecuted. What can I be prosecuted for if these photos are not covered by copyright (if I'm wrong, correct me). Example: http://www.pamatnik.valka.cz/index.php/fotografie/9-fotografie/dobove-fotografie/13-dobove-fotografie I would also like to ask if it is possible to freely use posters and postcards in the exhibition created by Vojtech Preissig (died in 1944). And my last. On the Internet, I came across a case where the authors of the site marked these historical photos with a large watermark. Example: http://www.karelvasatko.cz/historie-ceskoslovenskych-legii/dobove-fotografie/category/48-ruzne Thank you in advance for your answer, UV