Gutik, O.V., and O.B. Popadiuk. β€œOn the Semigroup $\boldsymbol{B}_{\omega}^{\mathscr{F}_n}$, Which Is Generated by the Family $\mathscr{F}_n$ of Finite Bounded Intervals of $\omega$”. Carpathian Mathematical Publications 15, no. 2 (August 9, 2023): 331–355. Accessed May 13, 2024. https://journals.pnu.edu.ua/index.php/cmp/article/view/6214.