Billings, W. D. (William Dwight), 1910-, <br/><br/>
Plants, man, and the ecosystem / 
by W. D. Billings. 
 - 2nd ed. 
 - London :  MacMillan.  1972. 
 - 160 pages ;  illustrations (maps) :  24 cm. 
 - Fundamentals of botany series .
<br/><br/>Bibliography: p. 149-151. 
<br/><br/><label>ISBN: </label>0333146336 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Botany--Ecology0