PiryatinskayaA. Yu., and SamoilenkoYu. S. 1995. “Wild Problems in the Theory of Representations of *-Algebras Generated by Generatrices and Relations”. Ukrains’kyi Matematychnyi Zhurnal 47 (1), 70–78. https://umj.imath.kiev.ua/index.php/umj/article/view/5384.