Towards First Urban Data Space in Bulgaria. - Vassil T. Vassilev; Dessislava Petrova-Antonova; Tarun Bali; Sorin Radu; Viktor Sowinski-Mydlarz; Dion Mariyanayagam; Evgeny Marinov; Petar O. Hristov; Sabin Nakarmi; Monika Rabka (ISC2, 2022)