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2. 2) T. Sunada: "Analysis on graphs and its applications" ed. by P. Exner, J.P. Keating, P. Kuchment, T. Sunada and A. Teplyaev, Proc. Sympos. Pure Math. 77 (American Mathematical. Society, Providence, RI, 2008) p. 51.
3. 3) M. Kotani, T. Shirai and T. Sunada (Eds.): "Discrete geometric analysis", Proc. of the 1st JAMS Symposium held in Sendai, December, 2002. Contemporary Mathematics 347 (American Mathematical Society, Providence, RI, 2004) p. 12.
4. 4) M. Kotani, M. Hino and T. Kumagai (Eds.): "Probabilistic approach to geometry". the 1st Conference of the Seasonal Institute of the Mathematical Society of Japan held at Kyoto University, Kyoto, July 28-August 8, 2008. Advanced Studies in Pure Mathematics 57 (Mathematical Society of Japan, Tokyo, 2010).
5. 5) M. Kotani, H. Naito and T. Tate (Eds.): "Spectral Analysis in Geometry and Number Theory", Contemporary Mathematics 484 (American Mathematical Society, Providence, RI, 2009).