Academician Veljko Milković is, among other things, known for his decades-long research of the Petrovaradin Fortress and its secrets. Numerous books and feuilletons that he published during his rich career speak in favor of this. A group of authors from the Department of Geography, Tourism and Hotel Management from the Faculty of Sciences at the University of Novi Sad published an international scientific research paper on the Petrovaradin Fortress entitled: "Sustainability of Underground Heritage, Example of Military Galleries of Petrovaradin Fortress in Novi Sad". The paper was published in English, and Veljko Milković is mentioned several times in the references of this paper.
In this paper, the authors Tamara Lukić, Tatjana Pivac, Marija Cimbaljević, Bojan Đerčan, Milka Bubalo Živković, Snežana Besermenji, Ivana Penjišević and Rajko Golić deal with the underground galleries of the Petrovaradin Fortress, their current state, analysis of the tourist offer of these galleries and achieve sustainability as a tourist facility. On several occasions throughout this paper Veljko Milković is mentioned as one of the important sources of information. The paper states, among other things:
The lack of financial resources for the implementation of all entrepreneurial ideas is also recognized in the decades-long appeals of Milković, a man who has dedicated a significant part of his working life to the study of the underground of the Petrovaradin Fortress.
The Petrovaradin Fortress was presented within the working group Underground Built Heritage Reuse and Valorisation Strategies on the COST action Underground4value as a good example of tourist valorised underground cultural heritage in Serbia.
For the purpose of this study, the authors used and listed 5 books by Veljko Milković that deal with the Petrovaradin Fortress and the perception of tourist potentials: Petrovaradin through legend and reality (Vrelo, 2001), Petrovaradin Fortress - Over and underground (Vrelo, 2005), Petrovaradin Fortress - Cosmic Labyrinth of Discovery (Vrelo, 2007), New Tourist Potentials (Vrelo, 2006) and Petrovaradin and Srem - Mystery of the Past (Society for the Popularization of Science, 2003).