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  1. Palynology and petrography of a Middle Devonian coal in Illinois /
    By: Peppers, Russel A. - Damberger, H. H.,
    Publication info: Urbana :Illinois State Geological Survey,1969.
    Contributed by: University of Illinois Urbana Champaign
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  2. Some fern-like fructifications and their spores from the Mazon Creek compression flora of Illinois (Pennsylvanian)
    By: Pfefferkorn, Hermann W. - Peppers, Russel A. - Phillips, Tom Lee,
    Publication info: Urbana,Illinois State Geological Survey,1971.
    Contributed by: University of Illinois Urbana Champaign
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  3. Spores in strata of late Pennsylvanian cyclothems in the Illinois Basin /
    By: Peppers, Russel A. - Illinois State Geological Survey.
    Publication info: Urbana, Ill. :Illinois State Geological Survey,1964.
    Contributed by: University of Illinois Urbana Champaign
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