Zalar, Dušan, Rasa Ušpalytė-Vitkūnienė, Danijel Rebolj, and Marjan Lep. “A Methodological Framework for Measuring the Level of Convenience of Transport Ticketing Systems”. Transport 33, no. 4 (December 5, 2018): 1005-1016. Accessed November 28, 2024. https://jest.vgtu.lt/index.php/Transport/article/view/167.