Schopf, J. M.; Wilson, L. R.; Bentall, R. (1944). An annotated synopsis of Paleozoic fossil spores and the definition of generic groups. Illinois State Geological Survey, Report of Investigations no. 91, 72 pp. plus plates.
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Schopf, J. M.; Wilson, L. R.; Bentall, R.
1944
An annotated synopsis of Paleozoic fossil spores and the definition of generic groups. Illinois State Geological Survey, Report of Investigations no. 91, 72 pp. plus plates