Author:

Gray,J.;Boucot,A.J.

Year:

1971

Title:

Early Silurian spore tetrads from New York earliest new world evidence for vascular plants.

Reference:

Gray,J. et al. (1971) Early Silurian spore tetrads from New York earliest new world evidence for vascular plants. Science Vol. 173 # 4000 P. 918- 921

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