NOTES
1. This paper was presented at the Commission III meeting of the International Cartographic
Association at UNESCO, Paris 1971.
2. These institutes are: The Department of Geographical Economy of the Economical University
Rotterdam - development of facilities for thematic mapping in economy; the Department of
Geochemistry of the Technical University Delft - development of facilities for trend surface
computation and representation; and the Foundation for Soü Mapping (STIBOKA, Wageningen) -
development of facilities for soil mapping.
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