Abbott, Maxine Langford. <br/><br/>
Lycopsid stems and roots and sphenopsid fructifications and stems from the upper Freeport coal of southeastern Ohio, 
by Maxine L. Abbott. 
 - Ithaca, N.Y.,  Paleontological Research Institution,  1968. 
 - 49 p.  illus.  31 cm. 
 - Palaeontographica Americana,  v. 6, no. 38 .
<br/><br/>Bibliography: p. 23-25. 
<br/><br/><label>LCCN: </label>gs 68000130 //r93 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Paleobotany--Pennsylvanian.<br/>Plants, Fossil--Ohio.
<br/><br/><label>LC Class. No.: </label>QE701  QE971  / .I82 v. 6, no. 38