Trukhan, Y. and Sheremeta, M.M. (2004) “Boundedness of the l-Index of the Naftalevich–Tsuji Product”, Ukrains’kyi Matematychnyi Zhurnal, 56(2), pp. 247–256. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/3748 (Accessed: 10 April 2025).