Drdla, P. . a Bulíček, J. . (2012) „FARE COLLECTION SYSTEM IN INTEGRATED PUBLIC PASSENGER TRANSPORT SYSTEMS", Perner’s Contacts, 7(2), s. 22–33. Dostupné z: https://pernerscontacts.upce.cz/index.php/perner/article/view/1137 (Viděno: 19 duben 2024).