【作者(必填)】
[size=0.875]Alan McCunn,[size=0.875]Wallace E. Huffman
【文题(必填)】 Convergence in U.S. Productivity Growth for Agriculture: Implications of Interstate Research Spillovers for Funding Agricultural Research【年份(必填)】
2000
【全文链接或数据库名称(选填)】https://onlinelibrary.wiley.com/doi/epdf/10.1111/0002-9092.00032#