ŠIMKOVIČ, Vladimír - ZAJÍČEK, Viliam - HAJTMANEK, Roman. User Tracking in VR Environment. In Proceedings - 2019 International Conference on Engineering Technologies and Computer Science : Innovation & Application. 1. vydanie. Piscataway, USA : Institute of Electrical and Electronics Engineers, 2019, S. 80-84. ISBN 978-1-7281-1915-1.