Mucka, P., G. J. Stein, and P. Tobolka. “Passsenger Ride Comfort and International Roughness Index Specifications in the Slovak Republic”. Communications - Scientific Letters of the University of Zilina, Vol. 21, no. 1, Feb. 2019, pp. 14-21, doi:10.26552/com.C.2019.1.14-21.