1. [1] Álvarez López, J. A., and A. Candel, “On turbulent relations,” to appear in Fundamenta Mathematicae, preprint, arXiv:1209.0307v8 [math.LO].
2. [2] Gao, S., Invariant Descriptive Set Theory, vol. 293 of Pure and Applied Mathematics (Boca Raton), CRC Press, Boca Raton, Fla., 2009.
3. [3] Gromov, M., “Groups of polynomial growth and expanding maps,” with an appendix by J. Tits, Publications Mathématiques Institut de Hautes Études Scientifiques, vol. 53 (1981), pp. 53–73.
4. [4] Gromov, M., Metric Structures for Riemannian and Non-Riemannian Spaces, vol. 152 of Progress in Mathematics, Birkhäuser Boston, Boston, 1999.
5. [5] Hjorth, G., Classification and Orbit Equivalence Relations, vol. 75 of Mathematical Surveys and Monographs, American Mathematical Society, Providence, 2000.