CENCELJ, Matija, GUTIK, Oleg in REPOVŠ, Dušan, 2022, On some generalization of the bicyclic semigroup: the topological version. Vìsnik Lʹvìvsʹkogo unìversitetu. Serìâ mehaniko-matematična = Visnyk of the Lviv University. Series mechanics and mathematics [na spletu]. 2022. Vol. 94, p. 56–71. [Dostopano 8 april 2025]. DOI 10.30970/vmm.2022.94.056-071. Pridobljeno s: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=slv&id=154164