- Bolton , R . 1966 . Defense Purchases and Regional Growth , 127 – 138 . Washington D.C. : The Brookings Institution .
- 2 Bolton op. cit. p 71
- Lankford , P. M . 1972 . Regional Incomes in the United States, 1929–1967 , 42 – 53 . Chicago : University of Chicago, Department of Geography . Research Paper No. 145
- 4 Lankford op. cit. pp 29 41
- Smith , D. M . 1959 . Industrial Locational and Regional Development—Some Trends in Northwest England . Environment and Planning , 1 : 173 – 191 .
- Meyer , J. R and Kuh , E . 1955 . Correlation and Regression Estimates when the Data are Ratios . Econometrica , 23 : 400 – 416 . Some part of the relationship may be owing to the use of ratios. For a summary of an endless debate, see
The Professional Geographer
Volume 27, 1975 - Issue 2