Pensa, Margus <br/><br/>
Variation in needle retention of scots pine in relation to leaf morphology, nitrogen conservation and tree age / 
M. Pensa. 
 - Tartu :  Tartu Univ. Press,  2003. 
 - 109 p.  ill. 
 - Diss. Biol. Univ. Tartuensis;  77 .
<br/><br/>Includes bibliogr. references 
<br/><br/><label>ISBN: </label>9985-56-745-5 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Biology<br/>Plant ecology