2003 ONS 2004 Ozawa et al 2003 Pareto 1896 Pastor & Stambaugh 2003 Pepper & Oliver 2006 Peterson 1993 Pettis 2001 Porter 2008 Ranaldo 2008 Reed & Hughes 2002 Reinhart & Rogoff 2009 Ricardo 1817 Robbins 1932 Ruhla 1992 Schrodinger 1944 Shiller 2010 Simkin & Roychowdhury 2006 Sinha 2005 Slani