1. J.L. Alperin, R.B. Bell, Groups and Representations, Graduate Texts in Mathematics, vol. 162 (Springer, New York, 1995)
2. L. Bartholdi, R.I. Grigorchuk, On the spectrum of Hecke type operators related to some fractal groups. Proc. Steklov Inst. Math. 231(4), 1–41 (2000)
3. L. Bartholdi, R.I. Grigorchuk, On parabolic subgroups and Hecke algebras of some fractal groups Serdica Math. J. 28(1), 47–90 (2002)
4. L. Bartholdi, R.I. Grigorchuk, V. Nekrashevych, From fractal groups to fractal sets, in Fractals in Graz 2001, Trends Math. (Birkhäuser, Basel, 2003), pp. 25–118
5. H. Bass, M.V. Otero-Espinar, D. Rockmore, Ch. Tresser, Cyclic Renormalization and Automorphism Groups of Rooted Trees, Lecture Notes in Mathematics, vol. 1621 (Springer, Berlin, 1996)