| A new spore genus from the Upper Pennsylvanian of Kansas, (abstr.) |
Clendening, J.A.; and Nygreen, P.W. |
American Journal of Botany vol. 55, no. 6, pt. 2, pp. 723-724 |
1968 |
N/A
|
| Morphological variation of Potonieisporites in a Late Pennsylvanian florule |
Nygreen, P.W.; and Bourn, O.B. |
Review of Palaeobotany and Palynology vol. 3, no. 1/4, pp. 325-332 |
1967 |
N/A
|
| Nanoxanthiopollenites, a new monolete miospore from the Upper Pennsylvanian of Kansas |
Clendening, J.A.; and Nygreen, P.W. |
Geoscience and Man vol. 15, pp. 125-128 |
1976 |
N/A
|