Trukhan Y, Sheremeta MM. Boundedness of the <em class="a-plus-plus">l</em>-Index of the Naftalevich–Tsuji Product. Ukr. Mat. Zhurn. [Internet]. 2004Feb.25 [cited 2024May4];56(2):247-56. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/3748