文献求助，谁能帮我找到必有重谢！

发到求助版无人理会，只好到这个专业论坛来了。希望版主放行，本人也曾多次为本版做过贡献，多谢！

要找的文献如下：

1、Proximity and knowledge sharing in clustered firms，International Journal of Globalisation and Small Business，Volume 4, Number 1 / 2010  

2、Cluster Absorptive Capacity：Why do Some Clusters Forge Ahead and Others Lag Behind? 作者：Elisa Giuliani，European Urban and Regional Studies July 2005 vol. 12 no. 3 269-288


3、Gatekeepers in regional networks of innovators， Cambridge Journal of Economics March 3, 2010


4、Regional Knowledge Networks: A Network Analysis Approach To the Interlinking of Knowledge Resources， European Urban and Regional Studies January 1, 2010 17: 83-97


5、The role of the firm's internal and relational capabilities in clusters: when distance and embeddedness are not enough to explain innovation ，Journal of Economic Geography March 1, 2009 9: 263-283


6、Do clusters really matter for innovation practices in Information Technology? Questioning the significance of technological knowledge spillovers，
Journal of Economic Geography February 1, 2011


如能找到，每篇文献悬赏20大洋。