Frederiksen, Norman O. <br/><br/>
Sporomorphs from the Jackson Group (Upper Eocene) and adjacent strata of Mississippi and western Alabama 

 - Washington, D.C.  U.S. Geological Survey  1980 
 - pp. 1-75  láms. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>EOCENO<br/>POLEN Y ESPORAS
<br/><br/><label>Subjects--Geographic Terms: </label><br/>ESTADOS UNIDOS