Paleozoic origin of the cycads /

Bibliographic Details
Main Author:	Mamay, Sergius H., 1920- (Author)
Format:	Government Document eBook
Language:	English
Published:	Washington : United States Department of the Interior, Geological Survey, 1976.
Series:	Geological Survey professional paper ; 934.
Subjects:	From 230 to 570 million years ago Cycads, Fossil. Paleobotany > Paleozoic. Paleobotany > West (U.S.) Paleobotany. Paleozoic Geologic Period. Southwest, New.
Online Access:	https://purl.fdlp.gov/GPO/gpo89675

by Mamay, Sergius H., 1920-

Government Document Book