d-mat/0205520. Bouchaud JP, Mezard M, 2000. Wealth Condensation in a Simple Model of Economy. Physica A282:536-545, cond-mat/0002374. Bouchaud JP, Farmer JD, Lillo F, 2009. How markets slowly digest changes in supply and demand. In Handbook of Financial Markets: Dynamics and Evolution, ed. T Hens, KR Sc