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Geology topics

G.M. Callahan

Publications and source records attributed to G.M. Callahan.

1 recordsLinked to original sources

The modernization program of the US Geological Survey's National Mapping Division

Discusses the components of the National Digital Cartographic Data Base of the USA, to be completed by the year 2000. Key tasks are; expand the digitising programme; modify data structures; develop digital revision capabilities; develop and adopt standards and implement quality control; support advanced analysis. -after Authors

Cartography and Geographic Information Systems