7Ayyagari, Meghana,Thorsten Beck, Asli Demirg - Kunt. Small and Medium Enterprises across the Globe [ J ]. Small Business Economics,2007,29 : (4) :415 -434.
8Bohon Patrick, Mathias Dewatripont. Contract Theory[ M ]. MIT Press, Cambridge, 2005.
9Frydman Roman, Cheryl Gray, Marek Hessel, Andrzej Rapaczynski. When Does Privatization Work? The Impact of Private Ownership on Corporate Performance in the Transition Economies [ J ]. The Quarterly Journal of Economies, 1999:1153 - 1191.
10Ivaldi Marc, Bruno Jullien, Patrick Rey, Paul Seabright, Jean Tirole. The Economics of Tacit Collusion [ R ]. Final Report for DG Competition, European Commission ,2003.