Deliverska, Mariela, Guenoveva Jecheva, Yanita Zherkova, Peter Stanchev, and Radoslav Pavlov. 2014. “The Fifth National Information Day: Open Access to Scientific Information and Data”. Digital Presentation and Preservation of Cultural and Scientific Heritage 4 (September):361-63. https://doi.org/10.55630/dipp.2014.4.47.