Author:

Clapham,W.B.

Year:

1970

Title:

Evolution of Upper Permian terrestrial floras in Oklahoma as determined from pollen and spores.

Reference:

Clapham,W.B. (1970) Evolution of Upper Permian terrestrial floras in Oklahoma as determined from pollen and spores. Proceedings of the North American Paleontological Convention. Field Museum of Natural History. Chicago, September 1969 Vol. 2 P. 411- 427

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