1. T. Bates, D. Pask, I. Raeburn and W. Szymanski, “The C*-algebras of row-finite graphs,” New York J. Maths. 6, 307–324 (2000).
2. J. F. Boutot and H. Carayol, “Uniformization p-adique des courbes de Shimura: les théorèmes de Cerednik et de Drinfeld,” in Courbes modulaires et courbes de Shimura (Orsay, 1987/1988), Astérisque 196–197 (7), 45–158 (1992).
3. Texts and Monographs in Physics;O Bratteli,1997
4. A. Carey, M. Marcolli and A. Rennie, “Modular index invariants of Mumford curves,” Noncommutative Geometry, Arithmetic, and Related Topics (Johns Hopkins Univ. Press, 2011), [arXiv:0905.3157].
5. J. Cuntz, “Simple C*-algebras generated by isometries,” Comm. Math. Phys. 57(2), 173–185 (1977).