Author:

Phillips,T.L.;Andrews,H.N.;Gensel,P.G.

Year:

1972

Title:

Two Heterosporous species of Archaeopteris from the Upper Devonian of West Virginia

Reference:

Phillips,T.L. et al. (1972) Two Heterosporous species of Archaeopteris from the Upper Devonian of West Virginia Pal¤eontographica Abteilung B Vol. 139 # 1 P. 47- 71

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