Perston, Richard J. <br/><br/>
North american trees 

 - Iown  Iowa state university   1948 
 - 399p., ill.,  18 cm 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Plant <br/>Forest <br/>Natural history
<br/><br/><label>Universal Decimal Class. No.: </label>58(7)  / PRI