ParasyukI. O., and SamoilenkoA. M. “On the Integral of a Function Along the Trajectories of a Nilpotent Flow”. Ukrains’kyi Matematychnyi Zhurnal 47, no. 6 (June 25, 1995): 837–847. Accessed July 27, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/5476.