Picketty, Thomas, 2014, Capital in the Twenty-First Century, The Belknap Press of Harvard University Press, Cambridge, USA.
Wilkinson, Richard and Pickett, Kate, 2010, The Spirit Level: Why Equality is Better for Everyone, Penguin Books, London.
Lansley, Stewart, 2012, The Cost of Inequality: Why Economic Equality is essential for Recovery, Gibson Square, 2012