The flora of the Ripley formation
Series: U.S. Geological survey.  Professional paper 136
Publisher: U.S.Govt.Print.Off.
Published: 1925
Place of publication: Washington
Language: eng
Number of pages: 94
Subjects: Paleobotany -- Cretaceous; Paleobotany
Notes: Bibliographical references.
At head of title: Department of the Interior.