Deng, Guixin; Yuan, Pingzhi On the structure of \(G(H,k)\). (English) Zbl 1286.05056 Algebra Colloq. 21, No. 2, 317-330 (2014). MSC: 05C20 05C25 05C38 PDFBibTeX XMLCite \textit{G. Deng} and \textit{P. Yuan}, Algebra Colloq. 21, No. 2, 317--330 (2014; Zbl 1286.05056) Full Text: DOI
Chen, Bo; Yuan, Pingzhi Normal congruence subgroups of Hecke groups. (English) Zbl 1162.20034 Algebra Colloq. 15, No. 4, 707-720 (2008). Reviewer: Nihal Yılmaz Özgür (Balikesir) MSC: 20H10 20H05 11F06 PDFBibTeX XMLCite \textit{B. Chen} and \textit{P. Yuan}, Algebra Colloq. 15, No. 4, 707--720 (2008; Zbl 1162.20034) Full Text: DOI Link