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Zones of influence of middle-size cities, their boundaries and passenger flows
Aynvarg, Ye. S., (1969)
Rassselenie v gorodach (kolic̆estvennye zakonomernosti) : sbornik statej
Davidovič, V. G., (1968)
Commuting and urbanization in the socialist countries of Europe
Fuchs, Roland J., (1977)