Hlavna, V. and Zvarkova, D. (1999) “A Mathematical Modelling of Nitrogen Oxide Formation in a cng Spark Ignition Engine”, Communications - Scientific letters of the University of Zilina, 1(4), pp. 37-48. Available at: http://journals.uniza.sk/index.php/communications/article/view/109 (Accessed: 6April2026).