Author:

Pfefferkorn,H.W.;Peppers,R.A.;Phillips,T.L.

Year:

1971

Title:

Some fern-like fructifications and their spores from the Mazon Creek compression flora of Illinois (Pennsylvanian).

Reference:

Pfefferkorn,H.W. et al. (1971) Some fern-like fructifications and their spores from the Mazon Creek compression flora of Illinois (Pennsylvanian). Illinois State Geological Survey, Circular # 463 P. 1- 56

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