Dunleavy, P.; Diwakar, R.; Dunleavy, C. (2007), The Effective Space of Party Competition(PDF), London School of Economics and Political Science, archived from the original(PDF) on 28 October 2007, retrieved 27 September 2011
Dunleavy, P.; Diwakar, R.; Dunleavy, C. (2007), The Effective Space of Party Competition(PDF), London School of Economics and Political Science, archived from the original(PDF) on 28 October 2007, retrieved 27 September 2011