3Ghosh and Yamarik. Are Regional Trading ArrangementsTrade Creating? An Application of Extreme Bounds Analysis[J ]. Journal of International Economics,2004,63 (2) : 369-395.
4Anderson. A heoretical Foundation for the Gravity Equa-tion [J ]. American Economic Review, 1997, 69 ( 1 ) : 106-116.
5Cheng and Wall. Controlling for Heterogeneity in GravityModels of Trade and Integration [J]. Federal Reserve Bank ofSt. Louis Review, 2005, 87( 1) : 49-63.
6Anderson and van Wincoop. Gravity with Gravitas : A So-lution to the Border Puzzle [J]. American Economic Review,2003,93(1):170-192.
7Baier and Bergstrand. Do Free Trade Agreements actuallyIncrease Members,International Trade [ J ]. Journal of Interna-tional Economics. 2007, (71) :72 -95.
8Wooldridge. Econometric Analysis of Cross - Section andPanel Data [M]. Cambridge,MA : MIT Press, 2002.
9Baier and Bergstrand. Economic Determinants of FreeTrade Agreements [ J ]. Journal of International Economics,2004,64 (1):29 - 63.
10Amalie Guillin. Trade in services and Regional TradeAgreements : do Negotiations on Services have to be Specific[EB ]. http : //www. google, com. hk/url ,2011.