1. Berry M.V.: Regular and irregular semiclassical wave functions. J. Phys. A. 10, 2083–91 (1977)
2. Berry, M.V.: Semiclassical mechanics of regular and irregular motion. Chaotic behavior of deterministic systems (Les Houches, 1981), 171–271, North-Holland, Amsterdam (1983)
3. Bourgain, J., Rudnick, Z., Sarnak, P.: Local statistics of lattice points on the sphere. to appear in Contemporary Mathematics, proceedings of Constructive Functions (2014)
4. Cilleruelo J., Córdoba A.: Lattice points on ellipses. Duke Math. J. 76(3), 741–750 (1994)
5. Colin de Verdière Y.: Ergodicité et fonctions propres du laplacien. Comm. Math. Phys. 102(3), 497–502 (1985)