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Optimal spatial interaction and the gravity model
Erlander, Sven, (1980)
An interaction model
Puu, Tönu, (1982)
Spatial interaction, transportation and interregional commodity flow models
Batten, David F., (1984)
Shortest-path distances : an axiomatic approach
Smith, Tony E., (1989)
A cost-efficiency theory of dispersed network equilibria
Smith, Tony E., (1988)
Africa and the World Population Conference
Smith, T. E., (1968)