A summary of phosphate-rock resources of the United States
Subtitle: an analysis of past estimates
By: James B. Cathcart, Richard P. Sheldon, and Robert A. Gulbrandsen ; United States Department of the Interior, Geological Survey.
Contributors: Sheldon, Richard Porter, 1923-; Gulbrandsen, Robert A.; Geological Survey (U.S.)
Series: Open-file report -- 81-789; Open-file report (Geological Survey (U.S.)) -- 81-789.
Publisher: The Survey
Published: 1981
Place of publication: [Reston, Va.?]
Language: eng
Format: Microform
Subjects: Phosphate rock -- United States.
Notes: Microfiche. [Denver, Colo. : U.S. Geological Survey, 1982?]. 1 microfiche ; 11 x 15 cm.

Bibliography: p. 9.