Statistics of self-crossings and avoided crossings of periodic orbits in the Hadamard-Gutzwiller modelPeter A. Braun, Stefan Heusler, Sebastian Müller and Fritz HaakeEur. Phys. J. B, 30 2 (2002) 189-206DOI: https://doi.org/10.1140/epjb/e2002-00374-7