PT Journal AU Varjan, P Gnap, J Semanova, S Stopka, O SO Transport And Communications PY 2017 BP 33 EP 36 VL 5 IS 2 DI 10.26552/tac.C.2017.2.8 WP https://tac.uniza.sk/artkey/tac-201702-0008.php SN 13395130 ER