Circulars listing open-file reports
Subtitle: years 1938 thru April 1974 : numbered for open-file reference.
Contributors: Geological Survey (U.S.)
Publisher: Open-File Services Section, U.S. Geological Survey
Published: 1975
Place of publication: Denver, Colo
Language: eng
Format: Microform
Subjects: Geology -- United States.
Other titles: Open-file report (Geological Survey (U.S.))