7Aschauer, David Alan. Is public expenditure productive[J]. Journal of Monetary Economics, 1989, (23):177-200.
8Adelheid Holl. Transport infrastructure, agglomeration economies, and firm birth: Em pirical evidence from portugal[J]. Journal of Regional Science,2004,44(4) : 693-712.
9Holtz-Eakin D. Public sector capital and the productivity puzzle[J]. Review of Econom- ics and Statistics, 1994,76(1) : 12-21.
10Kilkenny, Maureen. Transport costs and rural development[J]. Journal of Regional Science, 1998,38(2) : 293-312.